CX28331-1x - Conexant Systems, Inc.

Data Sheet 100985A

June 2, 2000

Advance Information

This document contains information on a product under development. The parametric information

contai ns target para me te rs tha t are subje ct to c hange.

NOTE(S):

The TX Monitor is only used with the 100-pin CX2833i-3X.

TPOS

TNEG

TCLK ENCODER

TAIS

Pulse

Shaper

E3MODE

LINE

DRIVER

PDB

DATA

MUX

RLOOP

ENDECDIS

LLOOP

LBO

XOE

TLINEP

TLINEM/N

DECODER

RPOS

RNEG

RCLK

RLOS

TCLK

Clock/

Data

Recovery

PDATA

PDATA/

NDATA

DATCLK

NReceiver

Monitor

ALOS

RLINEP

RLINEM/N

TMONP

TMONM

TXMON

TMONTST

REFCLK

REQH

LIU #1

LIU #2

LIU #3

CX28331/CX28332/CX28333

Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit

The CX28333 is a three-channel, E3/DS3/STS-1 fully-integrated Line Interface Unit

(LIU). It is configured via external pins and does not need a microprocessor interface.

Each channel has an independent equalizer on the receive side requiring no user

configuration. Also, each channel has a programmable transmit pulse shaper that can

be set to ensure that the cross-connect pulse mask requirement is met for transmit

cable length up to 450 feet. The CX28332 is a dual-channel, and the CX28331 is a

single-channel LIU with performance identical to the CX28333.

The CX28333 gives the user new economies of scale in concentrator applications

where three DS3 or STS-1 channels are concentrated into a single STS-3 channel. By

including three indepen dent transceivers on a chip, sign ifi cant external components are

eliminated, with the exception of 1:1 coupling transformers, termination resistors, and

supply bypass capacitors.

NOTE: In this document, "i" is used to represent the number of channels:

i = 1 (CX28331), i = 2 (CX28332), and i = 3 (CX28333).

Functional Block Diagram

Distinguishing Features

• Can be used as a data transceiver

over a maxi mum of 900 f eet of Type

734/728 coaxial cable or equivalent

in an on-premise environme nt

• Programmable pulse filtering to meet

cross-connect pulse masks (ANSI

T1.102-1993)

• Meets jitter specifications of Bellcore

GR499, GR253, and TBR 24 (with

external JAT).

• Large input dyn amic range

• Alarms for coding violation and loss

of sign al

• Full diagnostic loopback capability

• Uses a minimum of external

components

• Com pa ti ble with ITU-T G .703, G. 823

• Independent power down mode per

channel

• Easily interfaced to the DS3/E3

Framer IC (CX28342/3/4/6/8 and

CN8330)

• Selec table B3Z S/HDB3

encoding/decoding

• Sup eri or in pu t rec ei ver se n si t ivity

(< 25 mV)

• Transmit monitor inputs (CX2833i-3x

series only)

Physical Characteristics

• 80- and 100-pin ETQFP package

• Single 3.3 V pow er supply

• 1 W maximum power dissipation

(CX28333)

• –40 °C to +8 5 °C temp er a ture rang e

• 5 V-tolerant pins

• TTL digital pins

Applications

• Digital Cross-Connect Systems

•Routers

• ATM Switches

• Channelized Line Aggregation Units

• Tes t Eq uipment

• Channel Service Uni ts

• Multiplexers

100985A Conexant

Information in this document is provided in connection with Conexant Systems, Inc. (“Conexant”) products. These materials are

provided by Conexant as a service to its customers and may be used for informational purposes only. Conexant assumes no

responsibility for errors or omissions in these materials. Conexant may make changes to specifications and product descriptions at

any time, without notice. Conexant makes no commitment to update the information and shall have no responsibility whatsoever for

conflicts or incompatibilities arising from future changes to its specifications and product descriptions.

No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as

provided in Conexant’s Terms and Conditions of Sale for such products, Conexant assumes no liability whatsoever.

THESE MA TERIALS ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, RELA TING

TO SALE AND/OR USE OF CONEXANT PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A

PARTICULAR PURPOSE, CONSEQUENTIAL OR INCIDENTAL DAMAGES, MERCHANTABILITY, OR INFRINGEMENT OF ANY

PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. CONEXANT FUR THER DOES NOT WARRANT THE

ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE

MATERIALS. CONEXANT SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL

DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS, WHICH MAY RESULT FROM THE USE

OF THES E MATERIALS.

Conexant products are not intended for use in medical, lifesaving or life sustaining applications. Conexant customers using or selling

Conexant products for use in such applications do so at their own risk and agree to fully indemnify Conexant for any damages

resulting from such improper use or sale.

The following are trademarks of Conexant Systems, Inc.: Conexant™, the Conexant C symbol, and “What’s Next in Communications

Technologies”™. Product names or services listed in this publication are for identification purposes only, and may be trademarks of

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For additional disclaimer information, please consult Conexant’s Legal Information posted at www.conexant.com, which is

incorporated by reference.

Reader Response: Conexant strives to produce quality documentation and welcomes your feedback. Please send comments and

suggestions to tech.pubs@conexant.com. For technical questions, contact your local Conexant sales office or field applications

engineer.

CX28333EVM

CH2

CH3

CX28333

NRZTX DATA and CLK in

Loss of Signal

Code Violation

Clock Input

Control

TX B3ZS/HDB3 analog out

RX B3ZS/HDB3 analog in

NRZRX DATA and CLK out

NRZTX DATA and CLK in

NRZRX DATA and CLK out

NRZTX DATA and CLK in

NRZRX DATA and CLK out

CH1

CH2

CH3

CH1

TX B3ZS/HDB3 analog out

RX B3ZS/HDB3 analog in

TX B3ZS/HDB3 analog out

RX B3ZS/HDB3 analog in

100985_002

100985A Conexant

Ordering Information

Revision History

Model Nu mber Package Description Operating

Temperature

CX28331-1x 80-Pin ETQFP Single-channel LIU –40 °C to +85 °C

CX28332-1x 80-Pin ETQFP Dual-channel LIU –40 °C to +85 °C

CX28333-1x 80-Pin ETQFP Triple-channel LIU –40 °C to +85 °C

CX28331-3x 100-Pin ETQFP Single channel with Transmit Monitor in g –40 °C to +85 °C

CX28332-3 x 100-Pin ETQFP Dual channel with Transmit Monitoring –40 °C to +85 °C

CX28333-3 x 100-Pin ETQFP Triple channe l with Tr a nsmit Monitoring –40 °C to +85 °C

Revision Level Date Description

A—May 5, 2000 Initial Release

100985A Conexant

       
100985A Conexant v
   
        
Table of Contents
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  vii
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
0 Pin Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
1 Pin Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   1-1
0 Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    2-1
2 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2-3
2. 1 AMI B3ZS/HDB3 En coder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.2 Pulse Shaper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2.3 Line Driver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
2.3.1 Transmit Pulse Mask Templates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
2.4 Alarm  Indicatio n Signal (A IS) G enerator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2.5 Transmit Monitor Block (CX2833i-3x Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2.6 Jitter Generation (Intrinsic). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
3 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-10
3.1 Receive Sensitivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
3.2 AGC/VGA Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
3.3 Receive Equalizer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
3.4 The PLL Clock Recovery Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
3.5 Loss Of Signal (LOS) Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
3.6 B3ZS/HDB3 Decoder With Bipolar Violation Detector. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
3. 7 Data  Squelching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
4 Jitter Tolerance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-13
4.1 Jitter Transfer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
5 Additional CX28331/CX28332/CX28333 Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    2-16
5.1 Bias Generator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
5.2 Power-On Reset (POR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
5.3 Loopback Multiplexers (MUXes). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
6 Mechanical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-17
7 Electrical Characteristics  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-19

       
 Table of Contents CX28331/CX28332/CX28333
 Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit
vi Conexant 100985A
   
        
2.7.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
2.7.2 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
2.8 DC Characteristics  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-21
2.9 AC C haracteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   2-22
3.0 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1 PCB Design Considera tions for CX28331/CX2 8332/CX2 8333. . . . . . . . . . . . . . . . . . . . . . . . . . .   3-1
3.1.1 Power Supply and Grou nd Pl ane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1.2 Impedance Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.1.3 Other Passive Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.1.4 IBIS Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.1.5 Recommended Vendors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  A-1
A.1 Applicable Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   A-1
Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  B-1
B.1 Evalu ation Module Schem atic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   B-1

       
CX28331/CX28332/CX28333  List of Figures
Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit  
100985A Conexant vii
   
        
List of Figures
Figure 1-1. CX28331-1x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Figure 1-2. CX28332-1x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Figure 1-3. CX28333-1x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Figure 1-4. CX28331-3x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Figure 1-5. CX28332-3x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
Figure 1-6. CX28333-3x Pin Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Figure 2-1. Typical Application Of Single CX2833i Channel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Figure 2-2. Pulse Shaper. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Figure 2-3. Pulse Measurement Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Figure 2-4. Transmit Pulse Mask for DS3 Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Figure 2-5. Transmit Pulse Mask for STS-1 Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Figure 2-6. Transmit Pulse Mask for E3 Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Figure 2-7. AIS Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Figure 2-8. Minimum Jitter Tolerance Requirement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Figure 2-9. Maximum Jitter Transfer Curve Requirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Figure 2-10. CX2833i-1x Mechanical Drawing (80-Pin)—Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
Figure 2-11. CX2833i-3x Mechanical Drawing (100-Pin)—Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Figure 2-12. Timing Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Figure 3-1. Typical CX28333 Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Figure B-1. Recommended Schematic for the CX2833i-1x Device  . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Figure B-2. Recommended Schematic for the CX2833i-3x Device (1 of 2) . . . . . . . . . . . . . . . . . . . . . . B-3
Figure B-3. Recommended Schematic for the CX2833i-3x Device (2 of 2) . . . . . . . . . . . . . . . . . . . . . . B-4

List of Figures CX28331/CX28332/CX28333

Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

viii Conexant 100985A

CX28331/CX28332/CX28333 List of Tables

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit

100985A Conexant ix

List of Tables

Table 1-1. CX28331/CX28332/CX28333 Pin Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Table 1-2. CX2833i-3x Pin Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Table 2-1. DS3 Transmit Template Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

Table 2-2. STS-1 Transmit Template Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Table 2-3. Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19

Table 2-4. Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20

Table 2-5. DC Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21

Table 2-6. AC Characteristics (Logic Timing). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22

List of Tables CX28331/CX28332/CX28333

Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

xConexant 100985A

100985A Conexant 1-1

1.0 Pin Description

1.1 Pin Assignme nts

Figures 1-1 (CX28331-1x), 1-2 (CX28332-1x), and 1-3 (CX28333-1x) illustrate

pin assignments for the 80-pin Exposed Thin Quad Flat Package (ETQFP). See

Table 1-1 for the CX2833i-1x pin descriptions.

Figures 1-4 (CX28331-3x), 1-5 (CX28332-3x), and 1-6 (CX28333-3x)

illustrate pin assignments for the 100-pin ETQFP. The 100-pin package adds

more functionality, supporting new features such as Transmit Monitoring and

Transmit Monitoring Status testing. See Table 1-2 for the CX2833i-3x pin

descriptions.

The input/output (I/O) column is coded as follows:

I = Input

O = Output

I/O = Bidirectional

P = Power

NOTE: All digital inputs and outputs contain 75 kΩ pull-down resistors.

When a chann el is d isabled (i.e., th e PDx pin is t i ed l ow or not connect ed), a ll

receive and transmit analog circuitry powers down. Analog inputs (RLINE) are

ignored and analog outputs (TLINE) are high impedance. Digital inputs of a

powered-down channel are still active, but ignored. Overall noise on the device

can be lowered by not driving the digital inputs of a powered-down channel.

NOTE: When power is disconnected from the device, TLINE pins are low

impedance to ground if driven by more than one forward-bias diode

voltage (0.7 V) below ground. Additionally, driv ing TLINE, a

forward-bias diode voltage above the VGG pin, creates a low impedance

path from the TLINE pin to the VGG pin. Otherwise, the TLINE pins are

high impedance.

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-2 Conexant 100985A

Figure 1-1. CX28331-1x Pin Diagram

CX28331-1x

GPD

RESET

VGG

RBIAS

DVDDIO

LLOOP

RLOOP

ENDECDIS

DVDDC

TAIS

RLOS

RCLK

RPOS/RNRZ

RNEG/RLCV

REQH

REFCLK

TCLK

TPOS/TNRZ

TNEG/NC

DVSSC

E3MODE

LBO

XOE

VSS

VDD

DVSSIO

RVSS

RLINEN

RLINEP

RVDD

VDD

VSS

TVDD

TLINEN

TLINEP

TVSS

VSS

VDD

VSS

VDD

100985_003

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-3

Figure 1-2. CX28332-1x Pin Diagram

CX28332-1x

PD1

GPD

RESET

VGG

RBIAS

XOE1

LBO1

DVDDIO

LLOOP1

RLOOP1

RLOS1

RCLK1

RPOS1/RNRZ1

RNEG1/RLCV1

REQH1

TAIS1

TCLK1

TPOS1/TNRZ1

TNEG1/NC1

REFCLK1

E3MODE

ENDECDIS

DVDDC

DVSSC

PD2

RVSS2

RLINE2N

RLINE2P

RVDD2

XOE2

LBO2

DVSSIO

LLOOP2

RLOOP2

RLOS2

RCLK2

RPOS2/RNRZ2

RNEG2/RLCV2

REQH2

TAIS2

TNEG2/NC2

TPOS2/TNRZ2

TCLK2

REFCLK2

TVDD2

TLINE2N

TLINE2P

TVSS2

VSS

VDD

VSS

TVSS1

TVDD1

TLINE1N

TLINE1P

RVSS1

RLINE1P

RVDD1

RLINE1N

100985_004

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-4 Conexant 100985A

Figure 1-3. CX28333-1x Pin Diagram

CX28333-1x

PD1

GPD

RESET

VGG

RBIAS

XOE1

LBO1

DVDDIO

LLOOP1

RLOOP1

RLOS1

RCLK1

RPOS1/RNRZ1

RNEG1/RLCV1

REQH1

TAIS1

TCLK1

TPOS1/TNRZ1

TNEG1/NC1

REFCLK1

LLOOP2

RLOOP2

PD2

ENDECDIS

DVDDC

TAIS2

RLOS2

RCLK2

RPOS2/RNRZ2

RNEG2/RLCV2

REQH2

REFCLK2

TCLK2

TPOS2/TNRZ2

TNEG2/NC2

DVSSC

E3MODE

LBO2

XOE2

PD3

RVSS3

RLINE3N

RLINE3P

RVDD3

XOE3

LBO3

DVSSIO

LLOOP3

RLOOP3

RLOS3

RCLK3

RPOS3/RNRZ3

RNEG3/RLCV3

REQH3

TAIS3

TNEG3/NC3

TPOS3/TNRZ3

TCLK3

REFCLK3

RVSS2

RLINE2N

RLINE2P

RVDD2

TVDD3

TLINE3N

TLINE3P

TVSS3

TVDD2

TLINE2N

TLINE2P

TVSS2

TVSS1

TVDD1

TLINE1N

TLINE1P

RVSS1

RLINE1P

RVDD1

RLINE1N

100985_005

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-5

Table 1-1. CX2833i-1x Pin Definitions (1 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

Coaxial Line Pins

14 ——RLINEP Ch1 positive receive

data I Differential inputs for each channel

from its respective receive coax

line. The RX expects bal a nced

diffe r ential inp uts, usually achieved

using a 1:1 transformer.

The inputs are internally DC biased

to 1.9 V.

—66RLINE1P

15 ——RLINEN Ch1 ne ga ti ve r ece iv e

data I

—77RLINE1N

—22 14 RLINE2P Ch2 positive receive

data I

—23 15 RLINE2N Ch2 negative receive

data I

——22 RLINE3P Ch3 positive receive

data I

——23 RLINE3N Ch3 negative receive

data I

10 ——TLINEP Ch1 positive transmit

data O Differential, coax-driver balanced

outputs for pulse-shape d A MI

B3ZS/HDB3 en coded waveforms

for each cha nnel.

These pins should be connected to

the primary side o f the 1:1

transfor mer through two

backmatch resistors (see Appendix

B).

—2 2 TLINE1P

11 ——TLINEN Ch1 negative transmit

data O

—33TLINE1N

—18 10 TLINE2P Ch2 positive transmit

data O

—19 11 TLINE2N Ch2 negative transmit

data O

——18 TL INE 3P Ch3 posi tiv e transmit

data O

——19 TLINE3N Ch3 negative transmit

data O

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-6 Conexant 100985A

Digital Data Pins

54 ——RPOS/

RNRZ Ch1 receive Positive rail

or NRZ data O Resynchronized receive data

intended to be strobed out by the

corresponding RCLK.

When ENDECDIS = 1, these outputs

are positive and negative AMI data

(RPOS and RNEG).

When ENDECDIS = 0, these outputs

are decoded NRZ data (RNRZ) and

line c ode violation (RLCV). A line

code violation is indicated when

RLCV = 1.

See notes on the ENDECDIS pin in

the Contro l Signals section.

—68 68 RPOS1/

RNRZ1

55 ——RNEG/

RLCV Ch1 receive Negative rail

or line code violati on O

—69 69 RNEG1/

RLCV1

—33 54 RPOS2/

RNRZ2 Ch2 receive Positive rail

or NRZ data O

—32 55 RNEG2/

RLCV2 Ch2 receive Negative rail

or line code violati on O

——33 RPOS3/

RNRZ3 Ch3 receive Positive rail

or NRZ data O

——32 RNEG3/

RLCV3 Ch3 receive Negative rail

or line code violati on O

53 ——RCLK Receive clock Ch1 O Recovered clock for each channel

receiver, intended for strobing the

corresponding RDAT into the

following framer or logic.

—67 67 RCLK1

—34 53 RCLK2 Receive clock Ch2 O

——34 RCLK3 Receive clock Ch3 O

49 ——TPOS/

TNRZ Ch1 transmit Positive

rail or NRZ data I Sy nchronized transmit data

intended to be strobed in by the

corresponding TCLK.

When ENDECDIS = 1, these inputs

are expected to be positiv e and

negative AMI data (TPOS and

TNEG).

When ENDECDIS = 0, these inputs

are expected to be uncoded NRZ

data (TNRZ) and no connects (NC).

See notes on the ENDECDIS pin in

the Contro l Signals section.

—63 63 TPOS1/

TNRZ1

48 ——TNEG/

NC Ch1 transmit Negative

rail or no connect data I

—64 64 TNEG1 /

NC1

—38 49 TPOS2/

TNRZ2 Ch2 transmit Positive or

NRZ data I

—37 48 TNEG2 /

NC2 Ch2 transmit Negative

rail or no connect data I

——38 TPOS3/

TNRZ3 Ch3 transmit Positive or

NRZ data I

——37 TNEG3 /

NC3 Ch3 transmit Negative

rail or no connect data I

Table 1-1. CX2833i-1x Pin Definitions (2 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-7

50 ——TCLK T ransmit clock Ch1 I T ransmit bit clock input for strobing

with transm it data into the CX2833i.

—62 62 TCLK1

—39 5 0 TCLK2 Transm it cl oc k Ch2 I

——39 TCLK 3 Transm it clock Ch3 I

52 ——RLOS Loss of signal Ch1 O Loss Of Signal (LOS) indication for

each cha nnel, as det ermined by

insufficie nt puls e densit y. Signal

loss det ected when RLOS = 1. An

LOS will be ass e rte d w h en 175 ±75

0s occur in a row and deasserted

when the pu lse densi ty is between

28% and 33% (DS3/STS-1) (i.e., a

1s dens ity).

—66 66 RLOS1

—35 52 RLOS2 Loss of signal Ch2 O

——35 RLOS3 Loss of sign a l Ch3 O

Control Signals

59 59 59 ENDECDIS Encoder/decoder

disable (for all channels) I 1 = Dual rail pulse coded data

format. Input transmit data pins

TPOS, TNRZ, TNEG and NC ar e

inter preted as TPOS and TNEG

(encoded positive and negative rail

data). Out put receive data pins

RPOS and RNRZ, and RNEG and

RLCV are interpret ed as RPOS and

RNEG , w i th RPOS ha vi ng a positiv e

pulse in place of every positive AMI

pulse and RNEG ha ving a negative

pulse in place of every negative AMI

pulse.

0 = NRZ format. Transmit data pins

TPOS and TNEG are interpreted as

TNRZ and N C (not connected).

Receive d ata pins RPOS and RNEG

are interprete d as RNRZ and RLCV.

In this mode , all l ine c ode viol atio ns

are reported as active high on

RLCV.

51 ——TAIS Transmit Ch1 AIS mode

enable I Tr a nsmission of Alarm Indication

Signal (AI S) for a given channel.

Replace transmit data with AIS

signal. The AMI form of AIS

supported is alternating 1s.

(+1, -1, +1, -1, +1, ...)

Looping takes precedence over AIS.

1 = AIS mo de enabled

0 = AIS mo de disabled

—61 61 TAIS1

—40 51 TAIS2 Tra nsmit Ch2 AIS mode

enable I

——40 TAIS3 Tra nsmit Ch3 AIS mode

enable I

Table 1-1. CX2833i-1x Pin Definitions (3 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-8 Conexant 100985A

43 43 43 E3MODE E3MODE I When the pin is set to high, it

enables t he E3 mode on all

chan nel s, in stea d of t he DS 3/STS -1

mode. This also changes the pulse

shaper to E3 mode and overrides all

LBO pins. It also changes the

encod e r/decoder from B3ZS mode

to HDB3 mode.

1 = E3 mode

0 = DS3/STS-1 mode

44 ——LBO Tra ns m it lin e Ch1

build-out mode I Line bu il d- o ut mode per ch an ne l ,

based o n the lengt h of cable on the

transmit side of the cross-connect

block. This bit is overridden and the

pulse shaper is disabled (no pulse

shaping) if E3MODE = 1.

1 = Inserts line build- out into the

transm it channel. Usually used

when the transmit cable is less than

350 feet in length.

0 = Line build-out bypassed (not

inserted). Usually used when the

transmit cable is greater than 350

feet in length.

—72 72 LBO1

—29 44 LBO2 Transmit line Ch2

build-out mode I

——29 LBO3 Transmit line Ch3

build-out mode I

56 ——LLOOP Local loop back enabl e

Ch1 I Local loopback enable per channel.

The transmit data is looped back

immediat ely from the encoder to

the decoder in place of the received

data.

1 = local loopback enabled

0 = local loopback disabled

—74 74 LLOOP1

—27 56 LLO OP2 Local loopback enable

Ch2 I

——27 LLO OP3 Local loopback enable

Ch3 I

57 ——RLOOP Remote loopback enable

Ch1 I Remote loopback enable per

channel. The receive data, retimed

after clock recovery, is looped back

into the AMI generator in place of

the transmit data.

1 = remote loopback enabled

0 = remote loopback disabled

—75 75 RLOOP1

—26 57 RLOOP2 Remote loopback enable

Ch2 I

——26 RLOOP3 Remote loopback enable

Ch3 I

45 ——XOE Tr ans m it output enable

Ch1 I Transmit ou tput enable per chan nel.

1 = transmit line output driver

enabled

0 = transmit output driver set to

high impedance state

—71 71 XOE1

—30 45 XOE2 Transmit output enable

Ch2 I

——30 XOE3 Transmit output enable

Ch3 I

Table 1-1. CX2833i-1x Pin Definitions (4 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-9

46 ——REQH Ch1 Receive High EQ

Gain Enable I The equalizer in the CX2833i has

two gain settings. The higher gain

setti ng is designed to optima lly

equalize a nominally-shaped (meets

the pulse template), pulse-driven

DS3 or STS - 1 wav ef o rm that is

driven through 0–900 f eet of cabl e.

Square -shaped pulses such as E3

or DS3-HIGH require less

high-frequency gain and should use

the low EQ gain setting.

REQH = 1 high EQ gain

(DS3/STS-1 modes)

REQH = 0 low EQ gain (E 3/ DS3

Square Modes)

—70 70 REQH1

—31 46 REQH2 Ch2 Receive High EQ

Gain Enable

——31 REQH3 Ch3 Receive High EQ

Gain Enable I

Power/Ground

12 ——TVDD TX power Ch1 P Power pins for transmit c ircui try

per channel (3.3 V).

—4 4 TVDD1

—20 12 TVDD2 TX po wer Ch2 P

——20 TVDD3 TX po wer Ch3 P

9——TVSS TX ground Ch1 P Ground pins for transmit circuitry

per channel .

—1 1 TVSS1

—17 9 TVSS2 TX ground Ch2 P

——17 TVSS3 TX ground Ch3 P

13 ——RVDD RX power Ch1 P Power pins for receive circuitry per

chan nel (3.3 V) .

Connect to 3.3 V power.

—5 5 RVDD1

—21 13 RVDD2 RX power Ch2 P

——21 RVDD3 RX power Ch3 P

16 ——RVSS RX ground Ch1 P Ground pins for receive circuitry

per channel .

Connect to ground.

—8 8 RVSS1

—24 16 RVSS2 RX ground Ch2 P

——24 RVSS3 RX ground Ch3 P

60 60 60 DVDDC Digital core power P Digital core power for all channels

(3.3 V).

41 41 41 DVSSC Digita l core ground P Digit al core ground for all chan nels.

79 79 79 VGG 5 V/3.3 V ESD pin (1) P 5 V supply for 5 V-tolerant, digital

pad ESD diodes. No static power is

drawn from pin.

73 73 73 DVDDIO Digita l I/O power P Conn ect to 3.3 V digital pow e r.

28 28 28 D VSSIO Di gital ground P Digital ground.

Table 1-1. CX2833i-1x Pin Definitions (5 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-10 Conexant 100985A

4, 5, 20, 21 12, 13 —VDD Power P Connect to 3.3 V power.

1, 8, 17, 24 9, 16 —VSS Ground P Connect to ground.

Miscellaneous

58 ——PD Power down for Ch1 I Power do wn transceiver channel

0 = Power down channe l (off)

1 = Channel active (on)

Note: A special power-down mode

exists whe n all three PDBs ar e set

low . This special mode shuts of f the

entire chip (including biasing). This

is usefu l f or st atic Idd testing.

—76 76 PD1

—25 58 PD2 Power down for Ch2 I

——25 PD3 Power down for Ch3 I

47 ——REFCLK Reference clock for Ch 1 I Reference clock from off-chip.

This clock should be set to one of

the following:

•E3 rate (34.368 MHz)

•DS3 rate (44.736 MHz)

•STS-1 rate (51.84 MHz)

The clock rate should correspond to

the mode of operation that has been

chosen for the channel.

—65 65 REFCLK1

—36 47 R EFCLK2 Reference cloc k for Ch2 I

——36 REFCLK3 R eference cloc k for Ch3 I

80 80 80 RBIAS Bias r esistor O A 12.1 kΩ ± 1% resistor tie d from

this pin to ground provides the

current reference to the entire

chip.(2)

78 78 78 Reset Reset I/O Asynchron ous reset (reset entire

device).

77 77 77 GPD Global P ow e r down I/O Power down (Static Idd testing).

0 = Power down disable

1 = Power down active

2, 3, 6, 7, 18,

19, 22, 23,

25, 26, 27,

29, 30, 31,

32, 33, 34,

35, 36, 37,

38, 39, 40,

42, 61, 62,

63, 64, 65,

66, 67, 68,

69, 70, 71,

72, 74, 75,

10, 11, 14,

15, 42,

44–58

42 NC N o connect —Not connected.

NOTE(S):

(1) This pin should be connect ed to 3.3 V in an all- 3.3 V design.

(2) Placing a capacitor from t his pin to ground may result in instabili ties.

3. All digital i nput pins contain a 75 kΩ pull-down resistor from input to DVSS.

Table 1-1. CX2833i-1x Pin Definitions (6 of 6)

Pin # Signal Name Description I/O/P Notes

CX28331-1x CX28332-1x CX28333-1x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-11

Figure 1-4. CX28331-3x Pin Diagram

100985_015

100

DVDDC

ENDECDIS

RLOOP

LLOOP

RNEG/RLCV

RPOS/RNRZ

RCLK

RLOS

TAIS

TCLK

TPOS/TNRZ

TNEG/NC

TLOS

REFCLK

REQH

XOE

LBO

TMONTST

E3MODE

DVSSC

VSS

RBIAS

VGG

RESET

GPD

DVDDIO

VDD

VSS

TVSS

TMONP

TLINEP

TLINEM

TMONM

TVDD

RVDD

RLINEP

RLINEM

RVSS

VSS

VDD

VSS

DVSSIO

CX28331-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-12 Conexant 100985A

Figure 1-5. CX28332-3x Pin Diagram

100985_016

100

DVDDC

ENDECDIS

TMONTST

E3MODE

DVSSC

TVSS1

RBIAS

VGG

RESET

GPD

PD1

RLOOP1

LLOOP1

DVDDIO

LBO1

XOE1

REQH1

RNEG1/RLCV1

RPOS1/RNRZ1

RCLK1

RLOS1

REFCLK1

TLOS1

TNEG1/NC1

TPOS1/TNRZ1

TCLK1

TAIS1

TMON1P

TLINE1P

TLINE1M

TMON1M

TVDD1

RVDD1

RLINE1P

RLINE1M

RVSS1

VSS

VDD

VSS

TVSS2

TMON2P

TLINE2P

TLINE2M

TMON2M

TVDD2

RVDD2

RLINE2P

RLINE2M

RVSS2

PD2

RLOOP2

LLOOP2

DVSSIO

LBO2

XOE2

REQH2

RNEG2/RLCV2

RPOS2/RNRZ2

RCLK2

RLOS2

REFCLK2

TLOS2

TNEG2/NC2

TPOS2/TNRZ2

TCLK2

TAIS2

CX28332-3x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-13

Figure 1-6. CX28333-3x Pin Diagram

100985_006

100

DVDDC

ENDECDIS

PD2

RLOOP2

LLOOP2

RNEG2 / RLCV2

RPOS2 / RNRZ2

RCLK2

RLOS2

TAIS2

TCLK2

TPOS2/TNRZ2

TNEG2/NC2

TLOS2

REFCLK2

REQH2

XOE2

LBO2

TMONTST

E3MODE

DVSSC

TVSS1

RBIAS

VGG

RESET

GPD

PD1

RLOOP1

LLOOP1

DVDDIO

LBO1

XOE1

REQH1

RNEG1/RLCV1

RPOS1/RNRZ1

RCLK1

RLOS1

REFCLK1

TLOS1

TNEG1/NC1

TPOS1/TNRZ1

TCLK1

TAIS1

TMON1P

TLINE1P

TLINE1M

TMON1M

TVDD1

RVDD1

RLINE1P

RLINE1M

RVSS1

TVSS2

TMON2P

TLINE2P

TLINE2M

TMON2M

TVDD2

RVDD2

RLINE2P

RLINE2M

RVSS2

TVSS3

TMON3P

TLINE3P

TLINE3M

TMON3M

TVDD3

RVDD3

RLINE3P

RLINE3M

RVSS3

PD3

RLOOP3

LLOOP3

DVSSIO

LBO3

XOE3

REQH3

RNEG3/RLCV3

RPOS3/RNRZ3

RCLK3

RLOS3

REFCLK3

TLOS3

TNEG3/NC3

TPOS3/TNRZ3

TCLK3

TAIS3

CX28333-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-14 Conexant 100985A

Table 1-2. CX2833i-3x Pin Definitions (1 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

Coaxial Line Pins

17 ——RLINEP Ch1 posit ive

receive data I D ifferential inputs for each channel from its

respective receive coax line. The RX expects

balanced differential inputs, usually

achieved using a 1:1 transfo rm e r.

The in puts ar e inter n ally DC biased to 1.9 V.

—77RLINE1P

18 ——RLINEM Ch1 negative

receive data I

—88RLINE1M

—27 17 RL INE2P Ch2 positive

receive data I

—28 18 RLINE2M Ch2 neg ative

receive data I

——27 RL IN E3P Ch3 positive

receive data I

——28 RLIN E3M Ch3 neg a tive

receive data I

12 ——TLINEP C h1 positive

transmit data O Differential, coax-driver balanced outputs

for pulse-shaped AMI B3ZS/HDB3 encoded

waveforms for each channel .

These pins should be connecte d to the

primary side of the 1:1 transformer through

two backmatch resistors (see Appendix B).

—22TLINE1P

13 ——TLINEM Ch1 negative

transmit data O

—33TLINE1M

—22 12 TLINE2P Ch2 positive

transmit data O

—23 13 TLINE2M C h2 negative

transmit data O

——22 TLINE3P Ch3 positive

transmit data O

——23 TLINE3M Ch3 negative

transmit data O

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-15

Digital Data Pins

69 ——RPOS/

RNRZ Ch1 receive

Positive rai l or

NRZ data

O Resynchronized receive data intended to be

strobed out by the co rrespon ding RCLK.

When END ECDIS = 1, t hese outputs are

positive and negative AMI data (RPO S and

RNEG).

When END ECDIS = 0, t hese outputs are

decoded NRZ data (R NRZ) and li ne code

violat ion (RLC V). A line code violation is

indicat ed when RLCV = 1.

See notes on the ENDE CDIS pin in the

Control Signals section.

—84 84 RPOS1/

RNRZ1

70 ——RNEG/

RLCV Ch1 receive

Negative rail or

line code

violation

—85 85 RNEG1/

RLCV1

—41 69 RPOS2/

RNRZ2 Ch2 receive

Positive rai l or

NRZ data

—40 70 RNEG2/

RLCV2 Ch2 receive

Negative rail or

line code

violation

——41 RPOS3/

RNRZ3 Ch3 receive

Positive rai l or

NRZ data

——40 RNEG3/

RLCV3 Ch3 receive

Negative rail or

line code

violation

68 ——RCLK Receive clock

Ch1 O Recov ered clock for each channel receiver,

intended for str obing the corres pondin g

RDAT into the following framer or logic.

—83 83 RCLK1

—42 68 RCLK 2 Receive clock

Ch2 O

——42 RCLK3 Recei ve clock

Ch3 O

Table 1-2. CX2833i-3x Pin Definitions (2 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-16 Conexant 100985A

61 ——TPOS/

TNRZ Ch1 transmit

Positive rai l or

NRZ data

I Synchronized transmit data intended to be

strobe d in by the cor responding TCLK.

When ENDECDIS = 1, these inpu ts are

expected to be positive and negative AMI

data (TPO S an d TN EG) .

When ENDECDIS = 0, these inpu ts are

expected to be uncoded NRZ data (TNRZ)

and no connects (NC).

See notes on the ENDE CDIS pin in the

Control Signal section.

—78 78 TPOS1/

TNRZ1

60 ——TNEG/

NC Ch1 transmit

Negative rail or

no connect data

—79 79 TNEG1/

NC1

—47 61 TPOS2/

TNRZ2 Ch2 transmit

Positi ve or NRZ

data

—46 60 TNEG2/

NC2 Ch2 transmit

Negative data or

no connect data

——47 TPOS3/

TNRZ3 Ch3 transmit

Positi ve or NRZ

data

——46 TNEG3/NC3 Ch3 transmit

Negative data or

no connect data

62 ——TCLK Transmit clock

Ch1 I Transmit bit clock input for strobing with

trans mit data in to the CX2 833i .

—77 77 TCLK1

—48 62 TCLK2 Transmit clock

Ch2 I

——48 TCLK3 Transmit clock

Ch3 I

67 ——RLOS Loss of signal

Ch1 O Loss Of Signal (LOS) indication for each

channel, as determined by insufficient pulse

densit y. Signal loss detected when RLOS =

1. An LOS will be asserted when 175 ±75 0s

occur in a row and deasserted when th e

pulse de nsity is betwe en 28% and 33%

(DS3/STS-1) (i.e., a 1s density).

—82 82 RLOS1

—43 67 RLOS2 Loss of signal

Ch2 O

——43 RLOS3 Los s of signa l

Ch3 O

Table 1-2. CX2833i-3x Pin Definitions (3 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-17

Contr ol Si gn al s

74 74 74 ENDECDIS Encoder/decoder

disable (for all

channels)

I 1 = Du al rail pulse c od e d d ata fo rmat. Input

transmit data pins TPOS, TNRZ, TNEG and

NC are interpreted as TPOS and TNEG

(encoded positive and negative rail data).

Output receive data pins RPOS and RNRZ,

and RNEG and RLC V are interpreted as

RPOS and RNEG, with RPOS hav in g a

positive pulse in place of every positive AMI

pulse a nd RNEG having a negative pulse in

place of every negative AMI pulse.

0 = NRZ format. Tr ansmit data pins TP OS

and TNEG are interpreted as TNRZ and NC

(not connected). Receive data pin s RP OS

and RNEG are interpreted as RNRZ and

RLCV. In this mode, all line code violations

are reported as active high on RLC V.

63 ——TAIS Transmit Ch1

AIS mode ena bl e I Transmission of A larm Indication Signal

(AIS) for a given channel. Replace transmit

data with AIS signal. The AMI form o f AIS

supported is alternating 1s.

(+1, -1, +1, -1, +1, ...)

Looping takes precedence ov er AI S.

1 = AIS mo de enabled

0 = AIS mo de disabl ed

—76 76 TAIS1

—49 63 TAIS2 Transmit Ch2

AIS mode ena bl e I

——49 TAIS3 Transmit Ch3

AIS mode ena bl e —

53 53 53 E3MODE E3MODE I When the pin is set to high, it enables the

E3 mode on all channel s, instead of the

DS3/STS-1 mode. This also changes the

pulse shaper to E3 mode and overrides all

LBO pins. It also changes the

encoder/decoder from B3ZS mode to HDB3

mode.

1 = E3 mode

0 = DS3/STS-1 mode

55 ——LBO Tr ansmit line

Ch1 build-out

mode

I Line build-out mode per channel, based on

the leng th of cable on the transmit side of

the cross-connect block. This bit is

overridden and the pulse shaper is disabled

(no pulse sh aping) if E3 MODE = 1.

1 = Inse rts line build- out into the transmit

channel. Usually used whe n the transmit

cable is less than 350 feet in length.

0 = Line build-out bypassed (not inse rt ed).

Usually used when the tr ansmit cable is

greater than 350 feet in length.

—91 91 LBO1

—34 55 LBO2 Transmit line

Ch2 build-out

mode

——34 LBO3 Transmit line

Ch3 build-out

mode

Table 1-2. CX2833i-3x Pin Definitions (4 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-18 Conexant 100985A

71 ——LLOOP Local loo pback

ena ble Ch1 I Local loopback enable per channel. The

transmit data is looped back immediately

from the encoder to the decoder in place of

the received data.

1 = local loopback enabled

0 = local loopback disabled

—93 93 LLOOP1

—32 71 LLOOP 2 Local loopback

ena ble Ch2 I

——32 LLO OP3 Local loopback

ena ble Ch3 I

72 ——RLOOP Remote

loopback enable

Ch1

I Remote loopback enab le per channel. The

receive data, retimed after clock recovery , is

looped back into the AMI generator in place

of the transmit data.

1 = remote loopback enabled

0 = remote loopback disabled

—94 94 RLOOP1

—31 72 RLOOP2 Remote

loopback enable

Ch2

——31 RLOOP3 Remote

loopback enable

Ch3

56 ——XOE Transmit output

ena ble Ch1 I Transmit out put enable per channel.

1 = transmit line output d ri ver enab led

0 = transmit output driver set to high

impeda nce state

—90 90 XOE1

—35 56 XOE2 Transmit output

ena ble Ch2 I

——35 XO E3 Transmit outp ut

ena ble Ch3 I

57 ——REQH Ch1 Receive

High EQ Gain

Enable

I T he equa lizer in the CX2 83 3i has two gain

settings. The higher gain setting is designed

to optimally equalize a nominal ly-shap e d

(meets the pulse template), pulse-driven

DS3 or ST S- 1 wa ve fo r m that is dr ive n

thro ug h 0–90 0 feet of ca b le .

Square-shaped pulses such as E3 or

DS3-H IGH re quir e less high -fr equ ency gain

and shoul d use the low EQ gain setting.

REQH = 1 high E Q gain ( DS3/STS - 1 mod es )

REQH = 0 low EQ gain (E3/DS3

Square Modes)

—89 89 REQH1

—36 57 RE QH2 Ch2 Rece ive

High EQ Gain

Enable

——36 RE QH3 Ch3 Receive

High EQ Gain

Enable

Power/Ground

15 ——TVDD T X power Ch1 P Po wer pins for transmi t circuitry per

chan nel (3.3 V) .

55TVDD1

—25 15 TVDD2 TX pow er Ch2 P

——25 TVDD3 TX power Ch3 P

Table 1-2. CX2833i-3x Pin Definitions (5 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-19

10 ——TVSS TX ground Ch1 P Ground pins for transmit circuitry per

channel.

—100 100 TVSS1

—20 10 TVSS2 TX ground C h 2 P

——20 TVSS3 TX ground Ch3 P

16 ——RVDD RX power Ch1 P Power pins for receive circuitry per channel

(3.3 V).

Connect to 3.3 V power.

—6 6 RVDD1

—26 16 RVDD2 RX power Ch2 P

——26 RVDD3 RX power Ch3 P

19 ——RVSS R X ground Ch1 P Ground pins for receive circui try per

channel.

Connect to gro und.

—9 9 RVSS1

—29 19 RVSS2 RX ground Ch 2 P

——29 RVSS3 RX ground Ch3 P

75 75 75 DVDDC Digital core

power P Digital core power for all channels (3.3 V).

51 51 51 DVSSC Digital core

ground P Dig ital core ground for all channels.

98 98 98 VGG 5 V/3.3 V ESD

pin (1) P 5 V supply for 5 V - to le ra nt, digital pa d ES D

diodes. No stat ic power is drawn from pin.

92 92 92 DVDDIO Digital I/O power P Connect to 3. 3 V digital pow e r.

33 33 33 DVSSIO Digital ground P Digital ground.

5, 6, 25, 26 15, 16 —VDD P ow er P Connect to 3.3 V power.

9, 20, 29,

100 10, 19 —VSS Ground P Connect to ground.

Miscellaneous

73 ——PD Power down for

Ch1 I Power down transcei ver channel

0 = Power down chann e l (off)

1 = Channel active (on )

Note: A speci al power-down mode exists

whe n all three P DBs are se t low. This

special mod e shuts off the en tire chip

(including biasing). This is useful for static

Idd testing.

—95 95 PD1

—30 73 PD2 Power down for

Ch2 I

——30 PD3 Power down for

Ch3 I

Table 1-2. CX2833i-3x Pin Definitions (6 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-20 Conexant 100985A

58 ——REFCLK Reference clock

for Ch1 I R ef e r e nce clo c k f rom off-chip .

This clock should b e set to one of th e

following:

•E3 rate (34.368 MHz)

•DS3 rate (44.736 MHz)

•STS-1 rate (51.84 MHz)

The clock rat e should correspond to t he

mode of operation that has been chosen for

the channel.

—81 81 REFCLK1

—44 58 REFCLK2 Reference clock

for Ch2 I

——44 REFCLK3 Reference clock

for Ch3 I

99 80 99 RBIAS Bias resistor O A 1 2.1 kΩ ± 1% resi s tor tied fr o m thi s pi n

to ground provides the current reference to

the entire ch ip.(2)

97 97 97 Reset Reset I/O Asynchronous reset (reset entire device).

96 96 96 GPD Global Power

down I/O Power down (Static Idd testing).

0 = Power down disable

1 = Power down active

11 ——TMONP Ch1 positive

input I Transmit monitor input pins are no rmally

tied to thei r respective tra nsmit line

outputs, i.e., (TMON1P ⇒ TLINE1P and

TMON1M ⇒ TLINE1M).

Loss of signal output s are active hig h

when the mo nitor inpu ts detect no signal.

The TX monit or t est pin will assert all

TLOS output s when TM ONTST is high.

This is used to test board level functionality

downst ream from the TLOS outputs.

—11TMON1P

14 ——TMONM Ch1 negative

input I

—44TMON1M

—21 11 TMON2P Ch2 positive

input I

—24 14 TMON2M Ch2 negative

input I

——21 TMON3P Ch3 positive

input I

——24 TMON3M Ch3 negative

input I

59 ——TLO S TX los s of s i gnal

Ch1 Output O

—80 80 TLOS1

—45 59 TLOS2 TX loss of sign al

Ch2 Output O

——45 TLOS3 TX loss of s i gnal

Ch3 Output O

54 54 54 TM ONTST TX monitor test

pin I

Table 1-2. CX2833i-3x Pin Definitions (7 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

CX28331/CX28332/CX28333 1.0 Pin Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 1.1 Pi n Assignments

100985A Conexant 1-21

1–4, 7, 8,

21–24, 27,

28, 30–32,

34–50, 52,

64–66,

76–91,

93–95

11–14,

17–18,

37–39, 50,

52, 55–73,

86–88

37, 38 , 39,

50, 64 , 65,

66, 86 , 87,

52 No connect —Not connected.

NOTE(S):

(1) This pin should be connected to 3.3 V in an all-3.3 V design.

(2) Placing a capacitor f rom this pin t o ground may result in instabilit ies.

3. All digital input pins contain a 75 kΩ pull-down resistor from input to DVSS.

Table 1-2. CX2833i-3x Pin Definitions (8 of 8)

Pin # Sig nal Name Description I/O/P Notes

CX28331-3x CX28332-3x CX28333-3x

1.0 Pin Descriptio n CX28331/CX28332/CX28333

1.1 Pin Assignments Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

1-22 Conexant 100985A

100985A Conexant 2-1

2.0 Functional Description

2.1 Overview

CX28333 is a triple E3/DS3/STS-1 Line Interface Unit (LIU). It is the physical

la y er interface betw ee n the data framer (or other t erminal-side eq uipment) and t he

electrical cable used for data transmission.

The CX28333 LIU consists of three independent data transceivers that can

operate over type 734/728 coaxial cable at the rates of 34.368 Mbps (E3), 44.736

Mbps (DS3), and 51.84 Mbps (STS-1). The transmit side takes an NRZ or

already-encoded dual rail input and encodes it into AMI B3ZS (for DS3/STS-1)

or HDB3 (for E3) analo g w aveforms to be transmitted o v er t he coaxial cab le. The

receiver side takes in the attenuated and distorted analog receive signal and

equalizes, slices, and resynchronizes the signal before decoding it to the NRZ

output or sending out a non-decoded dual rail.

CX28331 and CX28332 are single- and dual-E3/DS3/STS-1 LIUs,

respectively. In all respects, their performance and features are identical to the

CX28333.

The architecture of the CX2833i includes the following internal functions for

each channel:

Transmitter:

• AMI B3ZS/HDB3 encoder

• pulse shaper

• line driver

• Alarm Indication Signal (AIS) insertion

• transmi t moni tor

Receiver:

• receive sensitivity

• Automatic Gain Control (AGC)

• receive equalizer

• Clock Recovery circuit

• Loss Of Signal (LOS) detector

• B3ZS/HDB3 decoder with bipolar violation detector

• data squelching

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.1 Overv iew Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-2 Conexant 100985A

Additional Fun ctions:

•bias generator

•power-on reset

•loopback MUXes

In addition, each channel has the ability to perform remote and local

loopbacks. Figure 2-1 illustrates a typical application using the CX2833i in a

channel.

External pins are provided to configure the various line rates and formats for

each channel.

The CX2833i is used as a data transceiver over a coaxial cable that is up to

900 feet long (or up to 450 feet from the DSX) in an on-premise environment

within any public or private networks which use these data rates.

Figure 2-1. Typical Application Of Single CX2833i Channel

0–450 ft COAX

(type 734/728) DSX

0–450 ft COAX

(type 734/728) DSX

0–450 ft COAX

(type 734/728)

0–450 ft COAX

(type 734/728)

100604_012

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.2 Transm itte r

100985A Conexant 2-3

2.2 Transmitter

This secti on describes th e detailed operat ion of the v arious b lock s in the CX2833i

transmitter.

2.2.1 AMI B3ZS/HDB3 Encoder

ENDECDIS and the E3MODE pins configure the encoder mode.

When ENDECDIS = 0, the encoder is receiving non-encoded Nonreturn to

Zero (NRZ) data on the TNRZ (TPOS) pin alone, and the NC (no connect)

(TNEG) pin is ignored.

Data is encoded into a representation of a three-level B3ZS (E3MODE = 0) or

HDB3 (E3MODE = 1) signal (conforming to the coding rules as specified in

Appendix A) before g oing on to t he pulse shaper in the form of tw o binary signals

repres enting the positive and negative thre e-level pulse s.

When ENDECDIS = 1, the encoder is disabled. The encoder passes

already-encoded data over TPOS (TNRZ) and TNEG (NC) to the pulse shaper.

The transmit digital data is clocked into the chip via a rising TCLK edge,

w hich must be equa l to the symbol rate ( line rat e). A small del a y added to t he data

provides a certain amount of negative data hold time.

2.2.2 Pulse Shaper

The pulse shaper converts the two digital (clocked) positive and negative pulses

into a single analo g three-le vel Alternate Mark In version (AMI) pulse. The pulses

are in Return to Zero (RZ) format, meaning that all positive and negative pulses

have a duration of the first half of the symbol period.

For the E3 rate (E3 MODE = 1), the AMI pulse is a full-amplitude,

square-sh aped pulse with very little slope.

Figure 2-2. Pulse Shaper

100604_008

Pulse

Shaper

LBO

Mode

LBO = 0

LBO = 1

+ Pulse – Pulse

Line Driver

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.2 Transmitter Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-4 Conexant 100985A

For DS3/STS-1 rates, a pulse-shaper block is used to shape the transmit

waveform and reduce its high-frequency energy content. This ensures that the

transmit pulse template is met at the cross-connect block, which follow s 0–450

feet of transmit-side coaxial cable.

2.2.3 Line Driver

The dif ferential lin e driv er takes t he filtered transmit w a v eform, increases it to the

proper level, and drives it into the transmit magnetics. The two external discrete

back-matchi ng re sist ors (36 Ω) aid in line matching. The driver is presented with

an approximately 150 Ω differential load. Driver gain accounts for the 6 dB gain

loss in the back-matching resistors.

Figure 2-3 illustrates th e Pulse/Power template mea s urement po ints for the

variou s data rates.

Figure 2-3. Pulse Measurement Points

0–450 ft COAX

(type 734/728) DSX

0–450 ft COAX

Pulse/Power Template for E3

Pulse/Power Template for DS3/STS-1

(type 734/728) DSX

0–450 ft COAX

(type 734/728)

0–450 ft COAX

(type 734/728)

100604_013

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.2 Transm itte r

100985A Conexant 2-5

2.2.3.1 Transmit Pulse

Mask Templates

Figure 2-4. Transmit Pulse Mask for DS3 Rates

Transmit Pulse Mask for STS-1 Rates

1 0.5 0 0.5 1 1.5

Normalized Symbol Time

Normalized Pulse Amplitude

1.2

0.8

0.6

0.4

0.2

100985_014

Table 2-1. DS3 Transmit Template Specifications

Time Axis Range (UI) Normalized Amplitude Equation

Upper Curve

–0.85 ≤ T ≤ –0.68 0.03

–0.68 ≤ T ≤ 0.36 0.03 + 0.5 {1 + sin [(pi / 2)(1 + T / 0.34)]}

0.36 ≤ T ≤ 1.4 0.08 + 0.407 e –1.84(T – 0.36)

Lower Curve

–0.85 ≤ T ≤ –0.36 –0.03

–0.36 ≤ T ≤ 0.36 –0.03 + 0.5{ 1 + sin[(pi / 2)(1 + T / 0.18)]}

0.36 ≤ T ≤ 1.4 0.03

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.2 Transmitter Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-6 Conexant 100985A

Figure 2-5. Transmit Pulse Mask for STS-1 Rates

Transmit Pulse Mask for STS-1 Rates

1 0.5 0 0.5 1 1.5

Normalized Symbol Time

Normalized Pulse Amplitude

1.2

0.8

0.6

0.4

0.2

100985_014

Table 2-2. STS-1 Transmit Template Specifications

Time A xis Ra ng e (T) Normalized Amplitude Equation

Upper Curve

–0.85 ≤ T ≤ –0.68 0.03

–0.68 ≤ T ≤ 0.26 0.03 + 0.5{1 + s in[(pi / 2)(1 + T / 0.34)]}

0.26 ≤ T ≤ 1.4 0.1 + 0.6 1 e –2.4(T – 0.26)

Lower Curve

–0.85 ≤ T ≤ –0.38 –0.03

–0.38 ≤ T ≤ 0.36 –0.03 + 0.5{1 + sin[(pi / 2)(1 + T / 0.18)] }

0.36 ≤ T ≤ 1.4 0.03

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.2 Transm itte r

100985A Conexant 2-7

Figure 2-6. Transmit Pulse Mask for E3 Rate

100985_007

17 ns

0.1

0.2

14.55 ns

8.65 ns

12.1 ns

24.5 ns

29.1 ns

Time

Volts

Normalized

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.2 Transmitter Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-8 Conexant 100985A

2.2.4 Alarm Indication Signal (AIS) Generator

When TAIS is asserted, an AIS replaces the transmit data at TPOS and TNEG.

The E3 type o f AIS signal (al l 1s) is suppo rted. In t hree-le ve l signal fo rm, this is a

continuously alternating positiv e and negative pulse stream, as if the transmit data

were a continuous string of logical 1s. Figure 2-7 illustrates the AIS signal.

The TAIS pin has the same data latenc y as the TX data pins and can be used to

replace single symbols within a data stream. When the encoder is disabled

(ENDECDIS = 1), the TAIS mode maintains the proper phase, based upon the

polarity of the last 1 received.

The AIS signal follows the same path as the TX data during remote or local

loopback.

2.2.5 Transmit Monitor Block (CX2833i-3x Only)

The transmit monitor i nputs (TMONP and TMONM) are designed to monitor t he

line driver outputs (TLINEP and TLINEM/N) for pulses and to assert a Loss Of

Signal (TLOS) indicator when no output pulse has been detected for 32 TCLK

periods. After TLOS is asserted, it will not deassert until a pulse is again

detec ted. The transmit monitor is an indepe ndent funct ion i n whi ch TMONP and

TMONM must be e xternally connec ted to TLINEP and TLINEM/N , respecti vel y.

A special pin (TMONTST) is available for testing board-level functionality

downstream from the TLOS outputs. When TMONST is high it will assert all

TLOS chan nel outputs. TLOS output s are acti v e high when t he monitor inputs do

not detect a signal.

Figure 2-7. AIS Signal

POSITIVE

PULSE

NEGATIVE

PULSE

TLINEP

(output voltage)

TLINEN

(output voltage)

8333_009

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.2 Transm itte r

100985A Conexant 2-9

2.2.6 Jitter Generation (Intrinsic)

The CX2833i device meet s the jitter generatio n requirements for various rates

with large margins, with the condition that the input transmit clock (TCLK) is

jitter-free. Data ra tes and jitter generation requirements are defined in the

following documents:

•E3 rate—ETSI TBR24, ITU-T 9.823

•DS3 rate—Bellcore Telecardia GR499, AT&T Accunet TR54014,

ITU-T 9.824

•STS-1 rate

—

Bellcore

Telecardia

GR253

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.3 Rece iv er Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-10 Conexant 100985A

2.3 Receiver

This secti on describes th e detailed operat ion of the v arious b lock s in the CX2833i

receiver.

2.3.1 Receive Sensitivity

The receiver recovers data from the coaxial cable that is attenuated due to the

frequency-dependent characteristics of the cable. In addition, the receiver

compensates for the flat loss (across all frequencies) in the various electrical

components and the variation in transmitted signal power.

The CX2833i device is able to recover data that has been attenuated by a

maximum of 900 feet of coax having characteristics and attenuation consistent

with ANSI T1.102-1993, Annex C, Figure C.2. This approximates the

characteristics of AT&T type 734/728 cable; almost the same attenuation

characteristic is achieved by one-half the length of AT&T type 735 cable.

2.3.2 AGC/VGA Block

The Variable Gain Amplifier (VGA) receives the AMI input signal from the

coaxial cable. The VGA supplies flat gain (independent of frequ enc y ) t o make up

for various flat losses in the transmission channel and for loss at one-half the

symbol rate that cannot be made up by the equalizer. The VGA gain is controlled

by a feedback loop which senses the amplitude of the equalizer output, acting to

servo this amplitude for optimal slicing.

2.3.3 Receive Equalizer

The receive equalizer receives the differential signal from a VGA and acts to

boost th e high fr equency content of th e signal t o redu ce inter - symbol interf erence

(ISI) to the point that correct decisions can b e made b y the slicer with a mi nimum

of jitter in the recovered data.

The REQH pin is provided to allow lower amounts of equalization (shorter

equivalent cable lengths) for cases where a square-shaped pulse (that does not

meet the DS3/STS-1 standards) is transmitted to the receiver. A square-shaped

input has a much larger high-frequency content and could have overshoots at the

EQ output high enough to cause bit errors. Setting REQH = 0 will lower the gain

and reduce the amount of overshoot.

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.3 Receiver

100985A Conexant 2-11

2.3.4 The PLL Clock Recovery Circuit

The clock rec overy circuit (RX PLL) e xtr acts the e mbedded clock from the sliced

data and provides this clock and the retimed data to the decoder (data mode).

Upon startup (after the internal reset is deasserted), the RX PLL uses a reference

clock (REFCLK, running at the symbol rate) and a phase-frequency detector to

lock to the correct data rate (reference mode). During reference mode, the data

outputs are squelched (set to 0). The RX PLL is kept in reference mode until a

valid inp ut is detect ed.

2.3.5 Loss Of Signal (LOS) Detector

The Receive Loss Of Signal (RLOS) is a digital function which monitors the

retimed data from the clock recovery block. The AMI data is checked for a

continuous run of zeroes. When a continuous run of 128 ± 1 consecutive zeroes

occurs, the RLOS signal is asserted. After the RLOS signal is asserted, a 1s count

is made on every block of 128 AMI symbols. The RLOS signal is deasserted

when the 1s count within a block of 128 symbols is at least:

B3ZS: Minimum 1s density = 39 ± 1 count out of 128 (~30.5%)

HDB3: Minimum 1s density = 29 ± 1 count out of 128 (~22.7%)

The RLOS detector will always monitor the cable-side RX inputs. The

detector is not affected by the state of remote or local looping.

2.3.6 B3ZS/HDB3 Decoder With Bipolar Violation Detector

In the CX2833i device, when ENDECDIS = 0 (encoder/decoder enabled), the

decoder takes the output from the clock recovery circuit and decodes the data

(HDB3 or B3ZS) into a single retimed NRZ data signal. The data signal is then

sent out of the CX2833i over the RNRZ (RPOS) pin. Any detected Line Code

Violations (LCV) are sent out over the corresponding RLCV (RNEG) pin. The

RLCV pin is asser ted for one symbol period at the time the violation appears on

the RX output pin (RNRZ).

The following shows data sequence criteria for LCV; violations are indicated

in bold text. A valid bipolar pulse is indicated by a B. A bipolar violation

(non-alter nating positive or negative) pu l se is i ndicated by a V.

•Excessive zeros: 0, 0, 0, 0 (HDB3) or 0, 0, 0 (B3ZS). These violations are

passed on as 0 data on the RNRZ pin.

•Bipolar violation: B, 0, V (i.e., +1, 0, +1 or -1, 0, -1 for HDB3 ) B, V

(B3ZS and HDB3). These violation s are passed on as 1 data on the RNRZ

pin.

•Coding violation: 0, 0, V (HDB3) or 0, V (B3ZS) with an even number of

Bs since the last valid 0 substitution V (follows coding rule). These

violations are passed on as 0 data on the RNRZ pin.

The e v en /odd co unter ( used to count the numbe r of Bs bet w een Vs) will co unt

a bipolar violation as a B. A coding violation or a valid 0 substitution resets the

counter.

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.3 Rece iv er Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-12 Conexant 100985A

When ENDECDIS = 1, the de coder is disabled, and th e re timed sl icer outputs

are sent out over RPOS (RNRZ) and RNEG (RLCV) pins. These outputs are then

decoded by the Framer or other downstream device. Line code violations are not

detected in this mode of operation. The decoder is configurable for either:

•E3 mode using HDB3 coding (E3MODE = 1)

•DS3/STS-1 mode using B3ZS coding (E3MO DE = 0 )

The receiver digital data outputs are centered on the rising edge of RCLK

(see Section 2.9).

2.3.7 Data Squelching

A counter in the receiver keeps track of the number of consecutive symbol

periods wit hout a v ali d data pulse. Wh en 128 or more 0s i n a ro w ar e counted, t he

receiver assumes that it has lost the signal and resets itself to try and regain the

signal. While the recei v er is reacquiring the signal, the clock re co ve ry b lock locks

to the ref erence cl ock an d the data squelchi ng i s achi eve d by forcing the data bits

to zero. The data squelching is tr ue in both NRZ and dual rail mode. When the

input signal has been properly amplified and equalized, the clock recovery PLL

will then switch to the inc oming data.

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.4 Jitter Tolerance

100985A Conexant 2-13

2.4 Jitter Tolerance

The CX2833i receiver is able to tolerate a specified amount of high-frequency

jitter in the received signal while providing error-free operation (generally

defined as a bit error rate of less than 10-9). The specifications (illustrated in

Figure 2-9) for jitter tolerance are discussed in the follow ing docume nts:

•E3 rate – IT U-T G . 823 and ETSI TBR24 contain fr equenc y mask s for input

jitter tolerance.

NOTE: To mee t jitter transfer requirements for loop-timed operation, an external

jitter atte nuator is required. The ji tter attenuator lessens jitter from the

receive clock.

•DS3 rate – ITU-T G.823 and Bellcore GR499 specify ji tter toleranc e

frequency masks for Category I and Category II interfaces.

•STS-1 rate – Bellcor e GR253 specifies a jitter tolerance. It is noted that the

STS-1 jitter tolerance differs from DS3 requirements only for Category II

interfaces.

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.4 Ji tter Tolera nc e Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-14 Conexant 100985A

Figure 2-8. Minimum Jitter Toler ance Requirement

DS3 / STS-1 Rates

1.0 UI

0.1 UI

1.0 UI

10 UI

0.1 UI

Jitter Frequency

Input Jitter AmplitudeInput Jitter Amplitude

E3 Rate

STS-1

DS3 Category I

DS3 Category II

100 Hz 1 kHz 10 kHz 100 kHz 1 MHz

10 Hz 100 Hz 10 kHz 100 kHz1 kHz

100604_014

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.4 Jitter Tolerance

100985A Conexant 2-15

2.4.1 Jitter Transfer

The receiver must meet ce rtain jitter tra nsfer specifications betw een the input and

output ji tter as a funct i on of f re quency. These specifications ar e only intended to

be met with the use of a jitter at tenuator. Because the C X2833i does not contain a

jitter attenuator, one will have to be supplied externally. For reference purposes,

the specifications are discussed in the following documents and shown in

Figure 2-9.

E3 rate—Assume the same as DS3.

DS3 rate—Bellcore GR499, section 7.3.2 and figures 7-3, 7-4, and 7-5,

defines and describes DS3 jitter transfer.

STS- 1 rate—Bellcore GR253, section 5.6.2.1, defines and describes jitter

transfer for the STS-1 rate.

Figure 2-9. Maximum Jitter Transfer Curve Requirement

0.1 dB

Jitter Frequency

Jitter Gain

–19.9 dB

STS-1 Category II

DS3 Category I

DS3 Category II

(Note: All slopes are 20 dB/decade)

10 Hz 100 Hz 1 kHz 10 kHz 100 kHz

100985_012

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.5 Additional CX2833i Functions Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-16 Conexant 100985A

2.5 Additional CX2833i Functions

2.5.1 Bias Generator

To achieve good isolation between the channels, each channel utilizes an

independent power and ground to both transmit and receive. Additionally, each

channel has its own band gap voltage reference. Because only one external

resistor for cu rrent generation e x ist s , only one band gap voltage can be used. The

band gap from Ch1 has been chosen for this task.

The 12.1 kΩ external resistor from pin RBIAS to ground, is specified to have

a tolerance of ±1%. This helps to keep tighter control on power dissipation and

circuit performance.

NOTE: Capacitance should be kept to a minimum on the RBIAS pin.

2.5.2 Power-On Reset (POR)

A POR function is provided in the CX2833i device to ensure all of the resettable

digital logic and analog control lines are starting from a known state. This circuit

uses a fixed RC timer (~1µs); add itionall y, 128 clocks from REFCLK a re counte d

(after t he R C t ime r has ti med- out ) b e for e reset i s deasserted, which be gins t i min g

after a minimum supply voltage is reached (see Table 2-4).

2.5.3 Loopback Multiplexers (MUXes)

Two loopback MUXes per channel in the CX2833i allow for local loopback

(terminal or framer side), remote loopback (cable side), or both (the AIS signal

follows the same path as the transmit data during loopback). The RLOS signal

monitors the RX cable inputs irrespective of any loopback.

In remote loopback, set by asserting pin RLOOP high, the receive data

(retime d after clock rec overy but not d ecoded) l oops back i nto the pulse sha per in

place of the transmit data. Additionally, this data sent out the RPOS, RNEG, and

RCLK pins.

In local loopback, set by asserting pin LLOOP, the transmit data loops back

immediately from the encoder output to the d ecoder inp ut in plac e of the recei v ed

data. Additionally, this data is sent out the TLINEP and TLINEM/N pins.

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.6 Mech an ic al Sp ec ific a tio ns

100985A Conexant 2-17

2.6 Mechanical Specifications

Figure 2-10. CX2833i-1x Me c hanic al Drawi ng (80- Pin)—D imensions

DD1D2

Pin #1

Ref. Mark

See DETAIL B

TOP

DETAIL B

BOTTOM

Dim.

Coplanarity

0.05

0.95

15.75

13.90

0.45

0.09

1.20 MAX.

12.35 REF.

6.50 REF.

1.00 REF.

0.32 REF.

0.65 REF.

0.10 MAX.

0.15

1.05

16.25

14.10

0.75

0.20

0.002

0.040

0.620

0.547

0.018

0.004

0.047 MAX.

0.486 REF.

0.256 REF.

0.039 REF.

0.013 REF.

0.026 REF.

0.004 MAX.

0.006

0.041

0.640

0.555

0.030

0.008

Ref. 80-Pin ETQFP (GP00-D537)

Millimeters Inches

Min. Max. Min. Max.

100985_008

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.6 Mechanical Specifications Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit

2-18 Conexant 100985A

Figure 2-11. C X2833i- 3x Mechanical Drawing (100-P in)—Dimensions

DD1D2

Pin #1

Ref. Mark

See DETAIL B

TOP

DETAIL B

BOTTOM

Dim.

Coplanarity

0.05

0.95

15.75

13.90

0.45

0.09

1.20 MAX.

12.00 REF.

8.00 REF.

1.00 REF.

0.22 REF.

0.50 REF.

0.08 MAX.

0.15

1.05

16.25

14.10

0.75

0.20

0.002

0.004

0.620

0.547

0.018

0.004

0.047 MAX.

0.472 REF.

0.315 REF.

0.039 REF.

0.009 REF.

0.020 REF.

0.004 MAX.

0.006

0.041

0.640

0.555

0.006

0.008

Ref. 100-Pin ETQFP (GP00-D543)mm

Millimeters Inches

Min. Max. Min. Max.

100985_008a

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.7 Electri cal Charact eristi c s

100985A Conexant 2-19

2.7 Electrical Characteristics

2.7.1 Absolute Maximum Ratings

Table 2-3. Absolute Maximum Ratings

Symbol Parameter Min Max Unit

DVDDC/

RVDD/

TVDD/

VDD

Powe r Supp ly Voltage –0.3 6 V

VIVoltage on Any Signal Pin –1.0 VGG + 0 .3 V V

TST St or a ge Temp erature –40 125 °C

TVSOL Vapor Phase Soldering

Temperature (1 min.) —220 °C

θJA Thermal Resistance (Still

air, soc keted) —40 °C/W

θJA Thermal Resistance (Still

air, soldered) —24 °C/W

θJc ——7.40 °C/W

FIT Failures in time @ 89,000

devic e hours, temperat ure

of 55 °C, 0 failures.

—313 fits

NOTE(S):

1. Stresses above those listed as abs olute maximum rat ings may cause permanent d amage

to the device. This is a stress rating only, and functional operation of the device at these or

any other co nditions beyond those in dicated in the other sections of this document is not

implied. Exposure to absolute maximum rating conditions for extended periods may affect

devic e reliability.

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.7 Ele ctr ic al Character i stics Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit

2-20 Conexant 100985A

2.7.2 Recommended Operating Conditions

Table 2-4 specifies various operating conditions, power supplies, and the bias

resistor.

Table 2-4. Recommended Operating Conditions

Parameter Conditions Min Nom Max Unit

Power supply voltage DVDDC, RVDD, TVDD,

VDD 3.135 3.3 3.465 V

ESD vo ltage(1) VGG 3.135 5 5.5 V

Power dissipation

(CX28333) Tota l ch ip —0.83 1.0 W

Power dissipation

(CX28332) Tota l ch ip ——0.8 W

Power dissipation

(CX28331) Tota l ch ip ——.450 W

External bias resistor Pin RBIAS to GND; ±1% 11.98 12.1 12.22 kΩ

NOTE(S):

(1) With 5 V lo gic i nput, VGG should be tied to 5 V. Wit h 3.3 V logic i nput, VGG s hould be tied

to 3.3 V.

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2.8 D C Characteri stics

100985A Conexant 2-21

2.8 DC Characteristics

Table 2-5. DC C haracterist ics

Parameter Conditions Min Nom Max Unit

Vih high threshold Digital inputs 2.0 —VGG + 0.3 V

Vil low threshol d Dig ital in pu ts –0.3 —0.8 V

Voh high threshold Digital outputs, Ioh = –4 mA 2.4 ——V

Vol low threshold Digital outputs, Iol = 4 mA —— 0.4 V

ILEAK 0 V ≤ digital Vin ≤ VGG –10 —200 µA

Input capacitance ———10 pF

Load capacitanc e Digital output s —— 15 pF

NOTE(S):

1. The digital inputs of CX2833i are TTL 5 V compliant. These inputs are diode protected to DVDDIO and DVSSIO pins.

Additionally, all of the CX2833i digital inputs contain 75 kΩ pull-do w n res i stors.

2. The digit al outputs of CX2833i are also TTL 5 V compl iant. However, these output s will not drive to 5 V, no r will they accept

5 V external pull-ups. The output is DVDDC (3.3 V).

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.9 AC Chara ct eris ti cs Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-22 Conexant 100985A

2.9 AC Characteristics

Table 2-6. AC Characteristics (Logic Timing)

Parameter Conditions Min Nom Max Unit

Tosym , Tisym

RCLK and TCLK E3

DS-3

STS-1

—29.10

22.35

19.29

—ns

Cloc k D uty Cycle Towidt h/ Tosym, R CLK

Tiwidth/Tisym, TCLK

Tiwidth/Tisym, REFCLK

—55

Todelay ———3ns

Tisetup TPOS/TNRZ, TNEG,

TAIS 4——ns

Tiho ld TPOS/TNRZ , TNE G,

TAIS 0——ns

NOTE(S):

1. The description applies to the DS3, E3, and STS-1 clock rates and other parameters such

as pu lse width, set-up time, hold time, and dut y cycle.

2. The tim in g d ia gram, i llu s t ra te d in Figure 2-12, describes the logical relationship between

various clock and da ta signals, and parameter values.

CX28331/CX28332/CX28333 2 .0 Functional Description

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 2. 9 AC Charac teristics

100985A Conexant 2-23

Figure 2-12. Timing Diagram

TCLK

TPOS/TNRZ,

TNEG, TAIS,

Tisym

Tisetup Tihold

DATA INPUTS

Don't

Care Valid Data

Tiwidth

RCLK

RPOS/RNRZ,

RNEG/RLCV

Tosym

Todelay

DATA OUTPUTS

Towidth

Don't

Care

100604_016

2.0 Functional Descriptio n CX28331/CX28332/CX28333

2.9 AC Chara ct eris ti cs Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

2-24 Conexant 100985A

100985A Conexant 3-1

3.0 Applicatio ns

The CX28331/CX28332/CX28333 can be used in a variety of applications.

Figure 3-1 illustrates an example of three DS3 lines being terminated by the

CX28333. The data and clock are extracted and passed on to the framer chip for

further data manipulation and user interface.

It is i mportant to employ high-frequ ency design technique s for the pri nted

board layout.

3.1 PCB Design Considerations for CX2833i

The CX28333 device is a triple LIU operating at frequencies up to 52.84 MHz.

The high-speed nature of the device calls for a careful design of the PCB using

this device. Some design considerations are outlined below.

3.1.1 Power Supply and Ground Plane

A unified power plane with properly placed capacitors of the correct size will

mitigate most power rail-related voltage transients. A properly placed bulk

capacitor, where the power enters the board, with noise-bypassing capacitors at

the powe r pins on the i ntegrated circui ts sho uld be adequ ate. T he noise-b yp assing

capacitors must be able to supply all the swi tching current.

Ferrite beads are used with power rails to filter the high-frequency noise. For

e v ery design, noise f reque ncies and le v els ar e dif fe rent. Th erefore, whether beads

are necessary, and the effective frequency where they should operate, is difficult

to determine. It is a good idea to provision for ferrite beads on the boards.

The board trace from the CX28333 power supply pin to the noise-bypassing

capacitor should be minimized. Additionally, ground connections from the

ground plane to the CX28333 ground pins and the noise-bypassing capacitor

ground pins should be minimized.

A unified ground plane is the best way to min imize ground impedan ce. Most

of th e ground noise i s produced by the return currents and p o w er suppl y transient s

during switching. This effect is minimized by reducing the ground plane

impedance.

3.0 Applic at i ons CX28331/CX28332/CX28333

3.1 PCB Design Considerations for CX2833i Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

3-2 Conexant 100985A

3.1.2 Impedance Matching

It is critical that traces around the transformers and matching resistors be kept to a

minimum length and, in the following cases, the trace impedance be matched to

75 Ω with a ±10% tolerance:

•The impedance from the BNC connector to the transformer

•The impedance from the transform er to the matching resi stors

3.1.3 Other Passive Parts

The reference design uses the Pulse T3001 extended temperature range 1:1

transformer for the coupling of the BNC connector to the device.

The ferrite beads used to decouple the receive- and transmit-VDD pins on all

analog input VDD pins are type 2508056017Y0 from Fair-Rite Products

Corporation. The bulk capacitor used for where the power enters the board

should be a tantulum–type capacitor, the recommended value and t ype is a 220 µf

tantulum capacitor.

3.1.4 IBIS Models

IBIS (Input/Output Buffer Interface Specification) models for the

CX28331/ CX28 332/ CX 2833 3- 1x and - 3 x are av ai l able from Cone xan t’s web site

(www.conexant.com).

3.1.5 Recommended Vendors

Product: Transfo rmers Product: Ferrite Beads

America

Address:

Telo:

Fax:

Pulse

Corporate Of fice

12220 Wor ld Trade Drive

San Diego, CA 92128

858-674-8100

858-674-8262 Telo:

Web site:

Fair-Rite Produ cts Corp.

P.O. Box J

One Commercial Row

Wallkil l, NY 12589

914-895-2055

www.Fair-Rite.com

Northern Asia

Telo:

Pulse

3F-4, No. 81, Sec. 1

Hsin Tai Wu Road

Hsi-Chih

Tapei Hs ien, Taiwan

R.O.C.

886-2-26980228

886-2-26980948

Product: Crystals

Northern Europe

Telo:

Fax:

Pulse

1S2 Huxley Road

The Surrey Research Park

Guildford, Surrey GU2 5RE

United Kingdom

44-1483-401700

44-1483-401701

Telo:

Fax:

E-mail:

Web site:

Crystek Corp.

12730 Commonwealth Dr ive

Fort Myers, FL 33913

800-237-3061

941-561-1025

sales@crystek.com

www.crystek.com

CX28331/CX28332/CX28333 3.0 Applications

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit 3.1 PCB Design Considerations for CX2833i

100985A Conexant 3-3

Figure 3-1.

NOTE(S):

1. All transforme rs are part nu mber T3001 from Pu lse Technology. See Recommen ded Vendors, Section 3.1.5.

2. TMONP and TMONM are only available on the CX2833i-3x device and are d e noted by dot ted lines .

TPOS

TNEG

TCLK

TLINEP

TLINEN

RLINEP

RNEG RLINEN

RPOS

RCLK

MODE BIAS RESET

Channel 1

CX28333

Framer

37.4

31.6

0.01µF

1:1

Type 728, 734, 735

TPOS

TNEG

TCLK TLINEN

RLINEP

RNEG RLINEN

RPOS

RCLK

MODE BIAS RESET

Channel 2

TLINEP

TMONP

TMONM

TMONP

TMONM

TMONP

TMONM

Framer

37.4

31.6

0.01µF

1:1

Type 728, 734, 735

TPOS

TNEG

TCLK TLINEN

RLINEP

RNEG RLINEN

RPOS

RCLK

MODE BIAS RESET

Channel 2

Framer

37.4

31.6

0.01µF

1:1

Type 728, 734, 735

MODE BIAS RESET

RBIAS 12.1K

Mode/Status Pins

100985_009

3.0 Applic at i ons CX28331/CX28332/CX28333

3.1 PCB Design Considerations for CX2833i Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

3-4 Conexant 100985A

100985A Conexant A-1

Appendix A

A.1 Applicable Standards

The applicable standards documents are as follows:

•ANSI T1.102-1993 (DS3 and STS-1 standard)

•ANSI T1.404a-1996 (DS3 metallic interface)

•ITU Recommendation G.703 (DS3 and E3 standard)

•ITU Recommendation G.823 and G.824 (jitter a nd wande r)

•Bellcore GR499, Issue 1, 12/89 (formerly TR-TSY-000499)

(DS3 and STS-1 requirements)

•Bellcore GR253, Issue 2, 12/91 (formerly TA-NWT-000253)

(STS-1 requirements and jitter)

•Bellcore TR-TSY-000191, Issue 1, 5/86 (AIS and LOS)

•ETSI TBR24 and TBR25 (E3 terminal equipment interface)

•ETSI ETS 300 686 and ETS 300 687 (E3 standard)

•AT&T Technical Reference TR54014, May 1992 (Accunet Interface

Specification for DS-3 jitter only)

Appendix A CX28331/CX28332/CX28333

A.1 Applicable Standards Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

A-2 Conexant 100985A

100985A Conexant B-1

Appendix B

B.1 Evaluation Module Schematic

Appendix B CX28331/CX28332/CX28333

B.1 Evaluation Module Schematic Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

B-2 Conexant 100985A

Figure B-1. Recommended Schematic for the CX2833i-1x Device

Position 7 REQH(1=Enable Equalization 0=Disable)

Pin 2 E3MODE 1=E3 mode is enabled 0=Disabled

Pin 1 ENDECDIS 1=Dual rail pulse coded data format

SOCKET

CHANNEL 3 RECEIVE

CHANNEL 3 TRANSMIT

CHANNEL 2 RECEIVE

DECODER AND E3 SELECTION

CHANNEL 1 RECEIVE

CHANNEL 1 TRANSMIT

CHANNEL 2 TRANSMIT

Position 1 PDB POWERDOWN (0=Powerdown 1=Active)

Position 2 RLOOP (1=Remote LPBK Enabled 0=Disabled)

Position 3 LLOOP (1=Local Loop Enabled 0=Disabled)

Position 4 LBO (1=TX CABLE less than 250ft 0=greater than 250ft)

Position 5 XOE (1=Transmitter Enabled 0=Disabled)

Position 6 TAIS (1=Enable AIS operation 0=disable)

DIGITAL GND

BNC

ANALOG GND

CCCC

2 Pin DIP Switch Setting

Seven Position DIP Switch Settings for all Channels

CH1_LOS

CH2_LOS

CH3_LOS

SW5

T3001

PULSE

T3001

PULSE

T3001

PULSE

T3001

PULSE

T3001

PULSE

37.4

0.01

R11

37.4

0.01

R12

37.4

T3001

PULSE

SW4

J10

21 CR3

C1 0.01

31.6

R10

L15

L11 L10

0.10.1

31.6

L13

L12

0.1

L14

0.1

12.1K

R13

CR1

CR2 SW9

0.1

510

14 SW1

510

SW2

510

14 SW3

R14

402

R15

402

R16

1/4

42.2

R17

C10

0.1

L16

L17

C11

0.1

32 68

40 62

80 ETQFP

CX28333

0.1

C12

C13

0.1

TAIS3/TMUXA4

XOE3

LBO3

LLOOP3

PDB3

RLOOP3

+3_3V

TAIS1/TMUXA2

XOE1

LBO1

LLOOP1

PDB1

RLOOP1

+3_3V

RLOS1

RLOS2

RLOS3

GND

OUT

VCC

+3_3V

+3_3V+3_3V

+3_3V

+5V

TMUXIO1

TMUXIO2

PDB1

RLOOP1

LLOOP1

LBO1

XOE1

REQH1/TMUXDAT

RNEG1/RLCV1

RPOS1/RNRZ1

RCLK1

RLOS1

REFCLK

TNEG1/NC1

TPOS1/TNRZ1

TCLK1

TAIS1/TMUXA2

PDB2

RLOOP2

LLOOP2

RNEG2/RLCV2

RPOS2/RNRZ2

RCLK2

RLOS2

TAIS2/TMUXA3

TPOS2/TNRZ2

REFCLK

REQH2/TMUXA0

XOE2

LBO2

TMUXLAT

PDB3

RLOOP3

LLOOP3

LBO3

XOE3

REQH3/TMUXA1

RNEG3/RLCV3

RPOS3/RNRZ3

RCLK3

RLOS3

REFCLK

TPOS3/TNRZ3

TAIS3/TMUXA4

+3_3V

+3_3V +3_3V

+3_3V

RLOOP2

PDB2

LLOOP2

LBO2

XOE2

TAIS2/TMUXA3

E3MODE

ENDECDIS

E3MODE

REQH1/TMUXDAT REQH2/TMUXA0

REQH3/TMUXA1

TMUXLAT

REFCLK

+3_3V

DVDD

DVDD2

DVSS

DVSS2

E3MODE

ENDECDIS

REQH3/TMUXA1

LBO1

LBO2

LBO3

LLOOP1

LLOOP2

LLOOP3

PDB1

PDB2

PDB3

RBIAS

RCLK1

RCLK2

RCLK3

REFCLK1

REFCLK2

REFCLK3

REQH1/TMUXDAT

REQH2/TMUXA0

RLINE1M

RLINE1P

RLINE2M

RLINE2P

RLINE3M

RLINE3P

RLOOP1

RLOOP2

RLOOP3

RLOS1

RLOS2

RLOS3

RNEG1/RLCV1

RNEG2/RLCV2

RNEG3/RLCV3 RPOS1/RNRZ1

RPOS2/RNRZ2

RPOS3/RNRZ3

RVDD1

RVDD2

RVDD3

RVSS1

RVSS2

RVSS3

TAIS1/TMUXA2

TAIS2/TMUXA3

TAIS3/TMUXA4 TCLK1

TLINE1M

TLINE1P

TLINE2M

TLINE2P

TLINE3M

TLINE3P

TMUXIO1

TMUXIO2

TMUXLAT

TNEG1/NC1

TPOS1/TNRZ1

TPOS2/TNRZ2

TPOS3/TNRZ3

TVDD1

TVDD2

TVDD3

TVSS1

TVSS2

TVSS3

VGG

XOE1

XOE2

XOE3

TCLK2

TNEG2/NC2

TCLK3

TNEG3/NC3

TCLK2

TNEG2/NC2

TCLK3

TNEG3/NC3

+3_3V

REQH2/TMUXA0

REQH3/TMUXA1

TAIS1/TMUXA2

TAIS2/TMUXA3

TAIS3/TMUXA4

REQH1/TMUXDAT

100985_017

CX28331/CX28332/CX28333 Appendix B

Single/Dual/Triple E3/DS3/STS-1 Lin e Interface Unit B.1 Evaluat ion Module Sche matic

100985A Conexant B-3

Figure B-2. Recommended Schematic for the CX2833i-3x Device (1 of 2)

Gnd Out

Vcc

Socket

CH1_RLOS

CH2_RLOS

CH3_RLOS

Position 7 REQH# ( 0 =EQ Disable 1 = EQ Enable)

Position 5 XOE# ( 0 = Tx Disable 1 = Tx Enable)

Position 2 RLOOP# ( 0 = RLPBK Disable 1 = RLPBK Enable)

Position 3 LLOOP# ( 0 = LPBK Disable 1 = LPBK Enable)

Position 4 LBO# ( 0 = Tx Cable > 250ft 1 = Tx Cable < 250ft)

Position 6 TAIS# ( 0 =Tx AIS Disable 1 = Tx AIS Enable)

Position 1 PDB# ( 0 = Powerdown 1 = Active)

Notes: Seven Position Dip switch for all Channels (SW1,2,3)

CX28333 DS3/E3/STS-1 LIU

CH1_TLOS

CH2_TLOS

CH3_TLOS

Pulse

2,3,4

Note: All capacitors are in Microfarads

Reset Device

BT01-D630- A

CX 28333 (LIU) w/Jitter Attenuator Circuit

Conexant Systems

9868 Scranton Road

San Diego,Ca 92121

Title

Size Document Number Rev

Date: Sheet of

PD3

RLOOP3

E3MODE

ENDECDIS

REFCLK

RPOS1/RNRZ1

REQH1/TMUXDAT

TCLK3

RLOS3

LLOOP1

XOE1

TMUXIO2

RCLK1

LBO3

REQH3/TMUXA1

LLOOP3

TAIS3/TMUXA4

LBO3

XOE3

PD2

RLOOP2

LLOOP2

LBO2

XOE2

TA IS2 /TMUXA3

REQH2/TMUXA0

RNEG1/RLCV1

RLOOP1

RCLK3

REQH3/TMUXA1

REQH2/TMUXA0

RPOS2/RNRZ2

TAIS2/TMUXA3

LBO2

E3MODE

TLOS2

TMUXLAT

RNEG2/RLCV2

RLOOP2

XOE2

TNEG1/NC1

REFCLK

TPOS2/TNRZ2

TNEG2/NC2

XOE3

RCLK2

TNEG3/NC3

RLOOP3

TLOS1

RPOS3/RNRZ3

TPOS3/TNRZ3

PD1

RLOS1

REFCLK

PD3

TMUXIO1

RNEG3/RLCV3

LLOOP2

TCLK2

TAIS3/TMUXA4

LLOOP3

RLOS2

TLOS3

TPOS1/TNRZ1

TCLK1

TAIS1/TMUXA2

PD1

LBO1

REQH1/TMUXDAT

LLOOP1

TAIS1/TMUXA2

RLOOP1

LBO1

XOE1

ENDECDIS

PD2

REQH1/TMUXDAT

REQH2/TMUXA0

REQH3/TMUXA1

TA IS1 /TMUXA2

TA IS2 /TMUXA3

TA IS3 /TMUXA4

RLOS1

RLOS2

RLOS3

TLOS1

TLOS3

TLOS2

TMUXIO1

TMUXLAT

TNEG1/NC1

TPOS1/TNRZ1

RCLK1

RNEG1/RLCV1

RPOS1/RNRZ1

RLOOP1

LLOOP1

LBO1

XOE1

TA I S1 /TMUXA2

REQH1/TMUXDAT

RLOOP3

REFCLK

TCLK3

TPOS3/TNRZ3

TNEG3/NC3

RCLK3

RPOS3/RNRZ3

RNEG3/RLCV3

LLOOP3

LBO3

PD3

XOE3

TAIS3/TMUXA4

REQH3/TMUXA1

PD2

RLOOP2

LLOOP2

LBO2

XOE2

TAIS2/TMUXA3

REQH2/TMUXA0

E3MODE

TMUXIO1

TMUXIO2

PD1

TMUXLAT

TNEG2/NC2

TPOS2/TNRZ2

TCLK2

RCLK2

RPOS2/RNRZ2

RNEG2/RLCV2

TCLK1

+3.3V

+5V

+3.3V

+3.3V +3.3V

+3.3V

T3001

1 6

3 4

J5 Channel 3 Transmit

R17

42.2

L11

bead

J1 Channel 1 Transmit

CR1

SW1

Chn 1

100

TMON1P

TLINE1P

TLINE1M

TMON1M

TVDD1

RVDD1

RLINE1P

RLINE1M

RVSS1

TVSS2

TMON2P

TLINE2P

TLINE2M

TMON2M

TVDD2

RVDD2

RLINE2P

RLINE2M

RVSS2

TVSS3

TMON3P

TLINE3P

TLINE3M

TMON3M

TVDD3

RVDD3

RLINE3P

RLINE3M

RVSS3

PD3

RLOOP3

LLOOP3

DVSSIO

LBO3

XOE3

REQH3

N/C1

N/C2

N/C3

RNEG3/RLCV3

RPOS3/RNRZ3

RCLK3

RLOS3

REFCLK3

TLOS3

TNEG3/NC3

TPOS3/TNRZ3

TCLK3

TAIS3

N/C4

DVSSC

NC11

E3MODE

TMONTST

LBO2

XOE2

REQH2

REFCLK2

TLOS2

TNEG2/NC2

TPOS2/TNRZ2

TCLK2

TAIS2

N/C5

N/C6

N/C7

RLOS2

RCLK2

RPOS2/RNRZ2

RNEG2/RLCV2

LLOOP2

RLOOP2

PD2

ENDECDIS

DVDDC

TAIS1

TCLK1

TPOS1/TNRZ1

TNEG1/NC1

TLOS1

REFCLK1

RLOS1

RCLK1

RPOS1/RNRZ1

RNEG1/RLCV1

N/C8

N/C9

N/C10

REQH1

XOE1

LBO1

DVDDIO

LLOOP1

RLOOP1

PD1

GPD

RESET

VGG

RBAIS

TVSS1

CR2

R23

37.4

SW2

Chn 2

J6 Channel 3 Receive

CR3

Red Led

0.01

JP6

1 2

L13

bead

0.1

JP7

1 2

1J21

0.1

JP8

1 2

31.6

SW9

1 4

2 3

31.6

L10

bead

T3001

1 6

3 4

0.1

T3001

1 6

3 4

C13

R10

31.6

0.1

37.4

R22

37.4

R36

T3001

1 6

3 4

44.736/34.368/51.256Mhz +/- 20ppm

7 8

141

R25

JP9

1 2

JP10

1 2

T3001

1 6

3 4

C10

0.1

JP11

1 2

R12

37.4

J3 Channel 2 Transmit

R18 0

SW4

R60

402

R52 0

37.4

0.01

J4 Channel 2 Receive

31.6

R61

402

R62

402

L16

bead

R13

12.1K

CR60

R19

R53

R14

402 CR61

L14

bead

C12

0.1

C11

0.1

R15

402 CR62

Red Led

SW7

R16

402

R24

R11

37.4

L12

bead

31.6

L15

bead

0.1

0.01

L17

bead

J2 Channel 1 Receive

SW3

Chn 3

R20 0

T3001

1 6

3 4

R21 0

SW10

1 4

2 3

100985_010

Appendix B CX28331/CX28332/CX28333

B.1 Evaluation Module Schematic Single/Dual/Tr iple E3/DS3/STS-1 Line Interface Unit

B-4 Conexant 100985A

Figure B-3. Recommended Schematic for the CX2833i-3x Device (2 of 2)

25V

1 square inch copper plane

used for heat sink

Optional external 3.3V Supply

Please remove JP3 when in

use

ConexantConexant

JitterJitter

AttenuatorAttenuator

BT01-D630- A

CX 28333 (LIU) w/Jitter Attenuator Evualation Module

Conexant Systems

9868 Scranton Road

San Diego,Ca 92121

Title

Size Document Number Rev

Date: Sheet of

REQH1/TMUXDAT

REQH2/TMUXA0

REQH3/TMUXA1

TA IS2 /TMUXA3

TA IS3 /TMUXA4

TA IS1 /TMUXA2

PD1

LLOOP1

PD2

LLOOP2

LBO2

TA IS2 /TMUXA3

PD3

LLOOP3

LBO3

REQH1/TMUXDAT

REQH3/TMUXA1

RLOOP1

E3MODE

XOE1

RLOOP2

XOE2

RLOOP3

XOE3

REQH2/TMUXA0

TMUXLAT

TMUXIO1

TMUXIO2

LBO1

TA IS1 /TMUXA2

TDI

VCO1

VCO1_CNTRL

DJATCLK1

VCO2

VCO2_CNTRL

VCO3

VCO3_CNTRL

VCO2_CNTRL

DJATCLK2

DJATCLK3

VCO3_CNTRL

CHANNEL3_STATUS

CHANNEL1_STATUS

TA IS3 /TMUXA4

+5VSRC

TMUXLAT

TNEG1/NC1

RNEG1/RLCV1

RCLK1

TCLK1

TPOS1/TNRZ1

TCLK2

RPOS1/RNRZ1

RCLK2

TPOS2/TNRZ2

RPOS2/RNRZ2

TNEG2/NC2

RNEG2/RLCV2

TCLK3

RCLK3

TPOS3/TNRZ3

RPOS3/RNRZ3

TNEG3/NC3

RNEG3/RLCV3

REFCLK

DJATCLK1

DJATCLK2

DJATPOS2

DJATPOS1

DJATNEG1

DJATNEG2

DJATCLK3

DJATPOS3

DJATNEG3

CHANNEL2_STATUS

TDI

RPOS3/RNRZ3

RPOS2/RNRZ2

DJATNEG2

RPOS1/RNRZ1

DJATNEG3

DJATPOS2

CHANNEL3_STATUS

DJATPOS3

TMS

DJATNEG1

DJATPOS1

CHANNEL2_STATUS

CHANNEL1_STATUS

VCO1

TDO

TCK

RCLK3

DJATCLK2

DJATCLK1

RCLK2

DJATCLK3

RNEG2/RLCV2

RNEG1/RLCV1

VCO2

TCK

TDO

TMS

RCLK1

RNEG3/RLCV3

VCO3

PD1 RLOOP1

LLOOP1

LBO1

PD2

LLOOP2

LBO2

LLOOP3

LBO3

TA IS1 /TMUXA2

XOE1

RLOOP2

XOE2

RLOOP3

XOE3

REQH1/TMUXDAT

TAIS3/TMUXA4

TAIS2/TMUXA3

TAIS1/TMUXA2

REQH3/TMUXA1

REQH2/TMUXA0

TMUXLAT

PD3

E3MODE

TMUXIO1

TMUXIO2

REQH3/TMUXA1

REQH1/TMUXDAT

TA IS2 /TMUXA3

REQH2/TMUXA0

TMUXLAT

TAIS3/TMUXA4

TCLK1

RPOS1/RNRZ1

TNEG1/NC1

RNEG1/RLCV1

TCLK2

RCLK2

TPOS2/TNRZ2

RPOS2/RNRZ2

TNEG2/NC2

RNEG2/RLCV2

TCLK3

RCLK3

TPOS3/TNRZ3

RPOS3/RNRZ3

TNEG3/NC3

RNEG3/RLCV3

REFCLK

RCLK1

TPOS1/TNRZ1

+3.3V

+5V

+3.3V

VCO DIJITCK2

7 8

141

J23

Black- Banana - Jack

D14

DIODE

J24

Blue Banana - Jack

VCO DIJITCK3

7 8

141

R34

1Meg

C26

JP2

Header

JP3

Header

JP1

Header

C20

0.1

J12

C18

0.1

R40

330

C19

0.1

C21

220

J15

J20

910

R27

330

CR13

Green Led

R28

330

R35

1Meg

C15

0.1

C22

C14

0.1

LT1086-3.3

3 2

GND

VIN VOUT

C24

0.1

C29

144 Pin - TQFP

108

107

106

105

104

103

102

101

100

144

143

142

141

140

139

138

137

136

135

134

133

132

131

130

129

128

127

126

125

124

123

122

121

120

119

118

117

116

115

114

113

112

111

110

109

RPOS3

RPOS2

GND_1

TDI

NC/1

NC/2

NC/3

NC/4

NC/5

RPOS1

NC/6

DJATNEG2

GND_2

NC/7

DJATNEG3

DJATPOS2

GND_3

STATUS3

DJATPOS3

TMS

NC/8

NC/9

NC/10

VCCIO_1

DJATNEG1

DJATPOS1

STATUS2

NC/11

NC/12

NC/13

NC/14

NC/15

GND_4

NC/16

NC/17

NC/18

NC/19

NC/20

NC/21

NC/22

NC/23

NC/24

NC/25

NC/26

NC/27

NC/28

NC/29

NC/30

NC/31

VCCIO_2

VCCI_1

GND_5

NC/32

VCO3

NC/33

NC/34

GND_6

VCCI_2

GND_7

NC/35

NC/36

NC/37

NC/38

GND_8

NC/39

NC/40

NC/41

NC/42

NC/43

NC/44

NC/45

NC/46

NC/73

NC/72

NC/71

GND_10

TDO

NC/70

NC/69

NC/68

NC/67

NC/66

NC/65

NC/64

NC/63

VCCIO_5

NC/62

NC/61

STATUS1

VCO1

NC/60

TCK

NC/59

NC/58

NC/57

GND_9

NC/56

NC/55

NC/54

NC/53

NC/52

NC/51

NC/50

NC/49

VCCIO_4

NC/48

NC/47

VCCIO_3

VCCIO_7

RNEG1

NC/89

RNEG2

NC/88

NC/87

NC/86

DJATCK3

RCLK2

GND_15

DJATCK1

RCLK1

RNEG3

DJATCK2

VCCI_4

GND_14

GND_13

RSTN

GND_12

RCLK3

GND_11

VCCI_3

NC/85

NC/84

NC/83

NC/82

NC/81

NC/80

NC/79

VCCIO_6

VCO2

NC/78

NC/77

NC/76

NC/75

NC/74

C25

0.1

R38

1Meg

C28

.1 C23

0.1

R32

1Meg

R37

1Meg

C16

0.1

J14

J22

Red - Banana - Jack

R33

1Meg

J13

C27

C17

0.1

R26

1Meg

VCO DIJITCK1

7 8

141

JP5

JP4

1 2

100985_011

Further Information:

literature@conexant.com

1-800-854-8099 (North America)

33-14-906-3980 (International)

Web Site

www.conexant.com

World Hea dquarters

Conexant Systems, Inc.

4311 Jamboree Road,

P.O. Box C

Newport Beach, CA 92658-8902

Phone: (949) 483-4600

Fax: (949) 483-6375

U.S. Florida/ South America

Phone: (727) 799-8406

Fax: (727) 799-8306

U.S. Los Angele s

Phone: (805) 376-0559

Fax: (805) 376-8180

U.S. Mid-Atlantic

Phone: (215) 244-6784

Fax: (215) 244-9292

U.S. North Central

Phone: (630) 773-3454

Fax: (630) 773-3907

U.S. Northeast

Phone: (978) 692-7660

Fax: (978) 692-8185

U.S. Northwest/Pacific West

Phone: (408) 249-9696

Fax: (408) 249-7113

U.S. South Central

Phone: (972) 733-0723

Fax: (972) 407-0639

U.S. Southeast

Phone: (919) 858-9110

Fax: (919) 858-8669

U.S. Southwest

Phone: (949) 483-9119

Fax: (949) 483-9090

APAC Headquarters

Conexant Systems Singapore,

Pte. Ltd.

1 Kim Seng Promenade

Great World City

#09-01 East Tower

Singapore 237994

Phone: (65) 737 7355

Fax: (65) 737 9077

Australia

Phone: (61 2) 9869 4088

Fax: (61 2) 9869 4077

China

Phone: (86 2) 6361 2515

Fax: (86 2) 6361 2516

Hong Kong

Phone: (852) 2 827 0181

Fax: (852) 2 827 6488

India

Phone: (91 11) 692 4780

Fax: (91 11) 692 4712

Korea

Phone: (82 2) 565 2880

Fax: (82 2) 565 1440

Europe Headquarte rs

Conexant Systems France

Les Taissounieres B1

1681 Route des Dolines

BP 283

06905 Sophia An tipolis Cedex

France

Phone: (33 4) 93 00 33 35

Fax: (33 4) 93 00 33 03

Europe Central

Phone: (49 89) 829 1320

Fax: (49 89) 834 2734

Europe Mediterranean

Phone: (39 02) 9317 9911

Fax: (39 02) 9317 9913

Europe North

Phone: (44 1344) 486 444

Fax: (44 1344) 486 555

Europe South

Phone: (33 1) 41 44 36 50

Fax: (33 1) 41 44 36 90

Middle E ast Headquarters

Conexant Systems

Commercial (Israel) Ltd.

P.O. Box 12660

Herzlia 46733, Israel

Phone: (972 9) 952 4064

Fax: (972 9) 951 3924

Japa n He adquarter s

Conexant Systems Japan Co., Lt d.

Shimomoto Buildin g

1-46-3 Hatsudai,

Shibuya-ku, Tokyo

151-0061 Japan

Phone: (81 3) 5371 1567

Fax: (81 3) 5371 1501

Taiwan Headquarters

Conexant Systems, Taiwan Co., Ltd.

Room 2808

International Trade Building

333 Keelung Road, Section 1

Taipei 110, Taiwan, ROC

Phone: (886 2) 2720 0282

Fax: (886 2) 2757 6760

Offi

ces