CX90240-11Z - Conexant Systems, Inc.

CX90240 CSM22

V.22bis Controller Serial Modem

with CX20548 SmartDAA

Data Sheet

DSH-201065F

May, 2012

5/18/12

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Revision History

Revision Date Description

A August 1, 2005 Initial release. Released as Doc. No. 102636A.

B March 30, 2006 Rev. B release. Released as Doc. No. 102636B.

C November 20, 2006 Rev. C release.

D October 14, 2009 Revision D release: conversion to FrameMaker

format

Corrected the pin numbers in “DTE Serial

Interface” section of Table 8. Changed the

description of DTR# in Table 8.

E July 6, 2010 Revision E release: changed 1.2 V to 1.8 V.

F May 18, 2012 Revision F release: Added package dimension

figures and tables for Punch and Sawn Styles.

5/18/12

Contents

Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.2.1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1.3 Technical Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1.3.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1.3.2 MCU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1.3.3 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1.3.3.1 Data Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1.3.3.2 Country Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1.3.4 Reference Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

1.4 Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

1.4.1 CX90240 V.22bis Modem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

1.4.2 Digital Isolation Barrier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

1.4.3 CX20548 SmartDAA Line Side Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

1.5 Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2 Technical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.1 Serial DTE Interface Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.1.1 Automatic Speed/Format Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.2 Establishing Data Modem Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.1 Dialing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.2 Modem Handshaking Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.3 Call Progress Tone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.4 Answer Tone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.5 Ring Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.6 Billing Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2.7 Connection Speeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.2.8 Automode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.3 Data Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.3.1 Speed Buffering (Normal Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.3.2 Flow Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.3.3 Direct Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

CX90240 CSM22 Data Sheet

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2.3.4 Escape Sequence Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.3.5 BREAK Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.3.6 Telephone Line Monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.3.7 Retrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.3.8 Programmable Inactivity Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.3.9 DTE Signal Monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.3.10 Call Progress Speaker Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.3.11 Serial EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4 Error Correction and Data Compression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4.1 V.42 Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4.2 MNP 2-4 Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4.3 V.42 bis Data Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.5 Telephony Extensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.5.1 Line In Use Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.5.2 Extension Pickup Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.5.3 Remote Hang-up Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.6 Point-of-Sales Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.7 Tone Detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.8 Caller ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.8.1 Type II CID. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.9 Country Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.10 Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2.10.1 Commanded Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2.11 Low Power Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

3 Hardware Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 31

3.1 CX90240 Modem Hardware Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1 CX90240 Modem Interface Signal Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1.1 LSD Interface (Through DIB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1.2 Call Progress Speaker Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1.3 Clock Select Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1.4 Serial EEPROM Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

3.1.1.5 Serial DTE Interface and Indicator Outputs . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.1.1.6 Control Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.1.1.7 Crystal/Clock and Power Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.1.2 CX90240 Modem Pin Assignments and Signal Definitions . . . . . . . . . . . . . . . . . . . . 33

3.1.3 CX90240 Modem Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

3.2 CX20548 LSD Hardware Pins and Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.1.1 Host Side Device (HSD) Interface (Through DIB) . . . . . . . . . . . . . . . . . . . . 39

3.2.1.2 Power and Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.1.3 Telephone Line Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.1.4 Voltage References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.1.5 General Purpose Input/Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.2.2 Pin Assignments and Signal Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3.3 Operating Conditions, Absolute Maximum Ratings, and Power Requirements . . . . . . . . . . 44

3.3.1 Handling CMOS Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

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CX90240 CSM22 Data Sheet

3.4 Crystal and Clock Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

4 Package Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 47

CX90240 CSM22 Data Sheet

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Figures

Figure 1. CX90240 CSM22 V.22bis Modem Simplified Interface . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 2. CX90240 Modem Hardware Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 3. CX90240 Modem 20-Pin QFN Pin Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 4. CX20548 LSD Hardware Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 5. CX20548 LSD 16-Pin QFN Pin Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 6. Package Dimensions for 20-Pin QFN, Punch Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Figure 7. Package Dimensions for 20-Pin QFN, Sawn Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Figure 8. CX20548 16-Pin QFN, Punch Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 9. CX20548 16-Pin QFN, Sawn Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

CX90240 CSM22 Data Sheet

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Tables

Table 1. CX90240 CSM22 V.22bis Modem Models and Functions. . . . . . . . . . . . . . . . . . . . . . . . 12

Table 2. Default Countries Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 3. Supported AT Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 4. +MS Command Automode Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Table 5. Supported Caller ID Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 6. Select Low-Power Mode (-SLP) Command Comparison Table . . . . . . . . . . . . . . . . . . . 29

Table 7. CX90240 Modem 20-Pin QFN Pin Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Table 8. CX90240 Modem Hardware Signal Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Table 9. CX90240 Modem I/O Type Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 10. CX90240 Modem DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Table 11. CX20548 LSD 16-Pin QFN Pin Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Table 12. CX20548 LSD Hardwar e Signal Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Table 13. CX2054 8 LSD GP IO DC Electr ic al Ch ar ac te rist ics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Table 14. CX20548 LSD AVDD and DVDD DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . 43

Table 15. CX90240 Modem Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Table 16. Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Table 17. Current and Power Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Table 18. Crystal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Table 19. Clock Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Table 20. Package Dimensions for 20-Pin QFN Punch and Sawn Styles. . . . . . . . . . . . . . . . . . . . 47

Table 21. Package Dimensions for 16-Pin QFN Punch and Sawn Styles. . . . . . . . . . . . . . . . . . . . 50

Tables CX90240 CSM22 Data Sheet

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1Introduction

1.1 Overview

The Conexant CSM22 V.22bis modem supports up to V.22bis data modem operation

with V.42 and MNP 2-4 error correction and V.42 bis data compression over a serial

host interface. Also, the V.80 synchronous access mode supports host-controlled

communication protocols. Major hardware interfaces and signal interfaces are

illustrated in Figure 1. Table 1 lists the ordering information.

The CSM22 device set consists of a CX90240 V.22bis Modem device in a 20-pin QFN

and a CX20548 SmartDAA 4 Line Side Device (LSD) in a 16-pin QFN.

The CX90240 V.22bis Modem integrates modem controller (MCU), serial host

interface, ROM code, RAM, and analog line interface codec onto a 20-pin Quad Flat

No-lead (QFN) package.

Conexant's SmartDAA technology used in the SmartDAA4 LSD eliminates the need

for bulky analog transformers, relays, and opto-isolators typically used in discrete DAA

implementations. The SmartDAA4 LSD operates without drawing power from the

phone line, unlike line-powered DAAs, and is therefore not subject to variations in line

voltage conditions. The SmartDAA4 LSD also adds enhanced telephony extension

features to the modem's operation and other functions such as Call Waiting detection,

and Caller ID decoding. Incorporating Conexant's proprietary Digital Isolation Barrier

(DIB) design and other innovative DAA features, the SmartDAA architecture simplifies

application design and minimizes layout area to reduce design cost.

The modem operates by executing masked code from internal ROM. The modem

features internal RAM memory that enhances the modem's flexibility. The modem's

internal RAM can be used to load new country profiles, override existing country

profiles or add customized firmware code. An optional external serial NVRAM is

supported. The optional external NVRAM adds the convenience of permanent

storage, just like internal RAM, NVRAM can be used to store new country profiles,

override existing ones or add customized firmware code.

A small, low profile package, low voltage operation, low power consumption, and low

Bill of Material (BOM) cost make this device set an ideal V.22bis solution for

embedded applications.

This data sheet describes the modem capabilities. Commands and parameters are

defined in the AT Commands Reference Manual (Doc. No. 102811).

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Introduction CX90240 CSM22 Data Sheet

Figure 1. CX90240 CSM22 V.22bis Modem Simplified Interface

Table 1. CX90240 CSM22 V.22bis Modem Models and Functions

Device Set Order Number Modem Device [20-Pin QFN]

Part Number Line Side Device (LSD) [16-Pin QFN]

Part Number

DS22-CSM-11Z CX90240-11Z CX20548-11Z (Device is marked 20548-A)

GENERAL NOTES: All devices are lead-free (Pb-free) and RoHS-compliant. These devices are compatible with leaded reflow processes.

CX90240 Modem

20-Pin QFN

MCU/DSP/

SmartDAA

Interface

DTE/Host

Interface

Serial

Interface

RAM

TIP

RING

External

Discrete

Components

Telephone

Line

Digital Isolation

Barrier (DIB)

CX20548

SmartDAA 4

Line Side Device (LSD)

16-Pin QFN

Line Side

DIB

Interface

(LSDI)

Codec

Telephone

Line

Interface

DAA Hardware

ROM

Optional

NVRAM

28.224 MHz

27.000 MHz

Crystal orClock

Source

5/18/12

CX90240 CSM22 Data Sheet Introduction

1.2 Features

Modulations

– ITU-T V.22bis (2400 bps)

– ITU-T V.22 and Bell 212A (1200 bps)

– ITU-T V.21 and Bell 103 (300 bps)

– ITU-T V.23 1200/75 and 75/1200

– V.23 Reverse Mode Protocol

Error correction protocols

– V.42 (LAPM)

– MNP2-MNP4

V.42bis Data Compression

DTE/host interface

– Serial DTE interface

– Direct Mode

– Asynchronous Mode

Selectable 27.000 MHz or 28.224 MHz crystal/clock support

Serial NVRAM support

Asynchronous Data Mode (Normal and Direct)

– 10- and 11-bit data

– DTE speeds up to 57,600 bps

– AT Command speed sensing from 300 bps to 57,600 bps

– RTS/CTS hardware flow control

– XON/XOFF software flow control

AT Command Set

– Command set includes common Hayes/legacy and V.250 commands.

Caller ID Decoding

– On-Hook Caller ID Type 1 decoding

– FSK decoder for Bell 202/V.23

– Call Waiting Caller ID (CWCID) Type 2 decoding

Sixty-four embedded and upgradeable country profiles

Ring detection

– Detection mode with no additional external components

SmartDAA

– Extension pick-up detection

– Digital line protection

– Remote hang-up/Line reversal detection

5/18/12

Introduction CX90240 CSM22 Data Sheet

– Worldwide compliance

Power

– Single +3.3 V supply

– Low power mode

– +3.3 V I/O level

Compact, robust board design

– Small, low-profile modem packages

– SmartDAA and DIB technologies

– Reference design supports 5 kV isolation

Small packages

– CX90240 Modem: 20-pin QFN CX20548 LSD: 16-pin QFN

Pin-to-pin compatible with CSMxx V.92/V.34/V.32bis modem

1.2.1 Applications

Set top boxes

Point-of-Sale terminals

ATM machines

Minitel terminals

1.3 Technical Overview

1.3.1 General Description

Modem operation, including dialing, call progress, telephone line interface, telephone

handset interface, and host interface functions are supported and controlled through

the AT command set.

The modem hardware connects to the host via a serial interface. The OEM adds a

crystal circuit or clock input, telephone line interface, and other supporting discrete

components as required by the application to complete the system.

1.3.2 MCU

The MCU performs processing of general modem control, command sets, data

modem, error correction, country configuration, V.80, serial host interface functions,

and signal processing.

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CX90240 CSM22 Data Sheet Introduction

1.3.3 Operating Modes

1.3.3.1 Data Modes

The modem operates in 2-wire full-duplex, asynchronous mode at line rates up to

2400 bps (V.22bis), 1200 bps (V.22 and Bell 212A), and 300 bps (V.21 and Bell 103).

V.23 full duplex (asymmetrical connect rate of 1200 bps in one direction and 75 bps in

the other direction) and V.23 half duplex mode (1200 bps) are also supported.

1.3.3.2 Country Operation

Country-dependent modem parameters for functions such as dialing, carrier transmit

level, calling tone, call progress tone detection, answer tone detection, blacklisting,

Caller ID, and relay control are programmable.

Internal ROM includes default profiles for 64 countries. Additional country profiles can

be uploaded to internal RAM (request additional country profiles from a Conexant

Sales Office) or to external serial NVRAM if supplied by the OEM. Duplicate country

profiles uploaded will override the default profiles in internal firmware. Country code

IDs are defined by ITU-TT.35. The default countries supported are listed in Table 2.

Table 2. Default Countries Supported (1 of 2)

Country Country Code Country Country Code

Argentina 7 Luxembourg 69

Australia 9 Malaysia 6C

Austria 0A Mexico 73

Belgium 0F Morocco 77

Brazil 16 Netherlands 7B

Bulgaria 1B New Zealand 7E

Canada 20 Norway 82

Chile 25 Pakistan 84

China 26 Philippines 89

Columbia 27 Poland 8A

Croatia FA Portugal 8B

Cyprus 2D Romania 8E

Czech Republic 2E Russia B8

Denmark 31 South Africa 9F

Egypt 36 Saudi Arabia 98

Estonia F9 Senegal 99

Finland 3C Singapore 9C

France 3D Slovakia FB

Germany 42 Slovenia FC

Greece 46 Spain A0

5/18/12

Introduction CX90240 CSM22 Data Sheet

1.3.4 Reference Design

An RS-232 external data modem reference de sign is available to minimize application

design time, reduce development cost, and accelerate market entry.

A design package is available in electronic form. This package includes schematics,

bill of materials (BOM), vendor part list (VPL), board layout files in Allegro format, and

complete documentation.

1.4 Hardware Description

1.4.1 CX90240 V.22bis Modem

The CX90240 V.22bis Modem, packaged in a 20-pin QFN, includes a Microcontroller

(MCU), internal ROM code, internal RAM, and analog line interface codec functions.

The modem connects to the host via a logical V.24 (EIA/TIA-232-E) serial DTE

interface.

The modem performs the command processing and host interface functions. The

crystal or clock input frequency is 28.224 MHz or 27.000 MHz.

The CX90240 connects to external serial EEPROM, if supplied by the OEM, via a

dedicated 2-line 400 kHz serial interface. The capacity of the EEPROM can be 256

bytes up to 32 Kbytes. The EEPROM can hold information such as patch code, OEM

configuration, customization, and country code parameters.

The modem performs telephone line signal modulation/demodulation in a hardware

digital signal processor (DSP) which reduces computational load on the host

processor.

Hong Kong 50 Sri Lanka A1

Hungary 51 Sweden A5

Iceland 52 Switzerland A6

India 53 Taiwan FE

Indonesia 54 Thailand A9

Ireland 57 Tunisia AD

Israel 58 Turkey AE

Italy 59 UK B4

Japan 0 UK Genesys FD

Korea 61 United Arab Emirates B3

Kuwait 62 Uruguay B7

Lebanon 64 USA B5

Table 2. Default Countries Supported (2 of 2)

Country Country Code Country Country Code

5/18/12

CX90240 CSM22 Data Sheet Introduction

1.4.2 Digital Isolation Barrier

The OEM-supplied Digital Isolation Barrier (DIB) electrically DC isolates the CX90240

from the LSD and telephone line. The modem is connected to a fixed digital ground

and operates with standard CMOS logic levels. The LSD is connected to a floating

ground and can tolerate high voltage input (comp atible with telephone line and typical

surge requirements).

The DIB transformer couples power and clock from the CX90240 to the LSD.

The DIB transformer also supports bidirectional half-duplex serial transfer of data,

control, and status information between the CX90240 and the LSD.

1.4.3 CX20548 SmartDAA Line Side Device

The CX20548 SmartDAA 4 Line Side Device (LSD) includes a Line Side DIB

Interface, a coder/decoder (codec), and a Telephone Line Interface (TLI).

The Line Side DIB Interface communicates with, and receives power and clock from,

the SmartDAA 4 interface in the host side device (HSD) through the DIB transformer.

The clock signal passing through the transformer is rectified in the LSD and filtered

using external capacitors.

Information is transferred between the LSD and the HSD through the DIB transformer

using pulse width modulation.

The TLI integrates DAA and direct telephone line interface functions and connects

directly to the line TIP and RING pins, as well as to external line protection

components.

Direct LSD connection to TIP and RING allows real-time measurement of telephone

line parameters, such as the telephone central office (CO) battery voltage, individual

telephone line (copper wire) resist a nce, and allows dynamic re gula tion of the off-hook

TIP and RING voltage and total current drawn from t he central of fice (CO). This allows

the modem to maintain compliance with U.S. and worldwide regulations.

5/18/12

Introduction CX90240 CSM22 Data Sheet

1.5 Commands

Modem functions operate in response to data modem and V.80 AT commands and S

Reference Guide (Doc. No. 102811) for a complete description of the commands and

registers.

Table 3. Supported AT Commands (1 of 3)

Command Description

$F Fast Connect Control

%C Enable/Disable Data Compression

%E Enable/Disable Line Quality Monitor and Auto-Retrain

%L Report Line Signal Level

%Q Report Line Signal Quality

%TT PTT Test Command

&C RLSD Option

&D DTR Option

&F Restore Factory Configuration (Profile)

&G Select Guard Tone

&K Flow Control

&M Asynchronous/Synchronous Mode Selection

&P Select Pulse Dial Make/Break Ratio

&Q Sync/Async Mode

&R RTS/CTS Option

&T Local Analog Loopback Test

&V Display Current Configuration and Stored Profiles

&V1 Display Last Connection Statistics

&X Select Synchronous Clock Source

** Load to Internal RAM

*B Display Blacklisted Numbers

*D Display Del ayed Numbers

\B Transmit Bre ak to Remote

\K Break Control

5/18/12

CX90240 CSM22 Data Sheet Introduction

\N Operating Mode

\V Single Line Connect Message Enable

+DR Data Compression Reporting

+DS Data Compression

+ER Error Control Reporting

+ES Error Control and Synchronous Mode Selection

+ESA Configure Synchronous Access Submode

+ESR Selective Repeat

+ETBM Call Termination Buffer Management

+GCI Country of Installation

+IBC In-Band Commands

+IFC DTE Modem Local Flow Control

+ITF Transmit Flow Control Thresholds

+MR Modulation Reporting Control

+MS Modulation Selection

+PCW Call Waiting Enable

+VCID Type I Caller ID (CID) Enable

+VDR Distinctive Ring

+VDT Control Tone Cadence Reporting

+VRID Report Retrieved CID

-HTRV History of Tip & Ring Voltage

-SCID Snooping CID (Type II)

-SLP Select Low-Power Mode

-STE Set Telephone Extension

-TRV Tip & Ring V oltage Measurement

-TTE Threshold Adjustments for Telephony Extension

AAnswer

BITU-T or Bell

Table 3. Supported AT Commands (2 of 3)

Command Description

5/18/12

Introduction CX90240 CSM22 Data Sheet

DDial

E Command Echo

H Disconnect (Hang-Up)

I Identification

L Speaker Volume

M Speaker Control

O Return to On-Line Data Mode

P Set Pulse Dial Default

Q Quiet Results Codes Control

S Read/Write S-Parameter

T Set Tone Dial Default

V Result Code Form

W Connect Message Control

X Extended Result Codes

Z Soft Reset and Restore Profiles

Table 3. Supported AT Commands (3 of 3)

Command Description

5/18/12

2Technical Specifications

2.1 Serial DTE Interface Operation

2.1.1 Automatic Speed/Format Sensing

Command Mode and Data Modem Mode. The modem can automatically determine

the speed and format of the data sent from the DTE. The modem can sense speeds of

300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 28800, 38400,

and 57600 bps and the following data formats:

The modem can speed sense data with mark or space parity and configures itself as

follows:

Parity Data Length

(No. of Bits) Number of

Stop Bits Character Length

(Number. of Bits)

None 7 2 10

Odd 7 1 10

Even 7 1 10

None 8 1 10

Odd 8 1 11*

Even 8 1 11*

*11-bit characters are sensed, but the parity bit is stripped off during data

transmission in Normal and Error Correction modes.

DTE Configuration Modem Configuration

7 mark 7 none

7 space 8 none

8 mark 8 none

8 space 8 even

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Technical Specifications CX90240 CSM22 Data Sheet

2.2 Establishing Data Modem Connections

2.2.1 Dialing

Pulse Dialing. Pulse dialing is supported in accordance with EIA/TIA-496-A.

Blind Dialing. The modem can blind dial in the absence of a dial tone if enabled by the

X0, X1, or X3 command.

2.2.2 Modem Handshaking Protocol

If a tone is not detected within the time specified in the S7 register after the last digit is

dialed, the modem aborts the call attempt.

2.2.3 Call Progress Tone Detection

Ringback, equipment busy, congested tone, warble tone, and progress tones can be

detected in accordance with the applicable standard.

2.2.4 Answer Tone Detection

Answer tone can be detected over the frequency range of 2100 ± 40 Hz in ITU-T

modes and 2225 ± 40 Hz in Bell modes.

2.2.5 Ring Detection

Conventional discrete DAA designs include a ring detection circuit. To reduce BOM

cost, the CX90240 device eliminates the need for this circuit. A ring signal is detected

from the receive analog input by qualifying the line's characteristics through a given

set of parameters defined in the country profiles and configured by an AT command.

Country parameters define the frequency range and time duration of the ring signal.

2.2.6 Billing Protection

When the modem goes off-hook to answer an incoming call, both transmission and

reception of data are prevented for 2 seconds to allow transmission of the billing tone

signal.

5/18/12

CX90240 CSM22 Data Sheet Technical Specifications

2.2.7 Connection Speeds

Line connection can be selected using the +MS command. The +MS command

selects modulation, enables/disables automode, and selects minimum and maximum

line speeds (Table 4).

2.2.8 Automode

Automode detection can be enabled by the +MS command to allow the modem to

connect to a remote modem (Table 4).

2.3 Data Mode

Data mode exists when a telephone line connection has been established between

modems and all handshaking has been completed.

2.3.1 Speed Buffering (Normal Mode)

Speed buffering allows a DTE to send data to, and receive data from, a modem at a

speed different than the line speed. The modem supports 64-byte buffering at all line

speeds.

2.3.2 Flow Control

DTE-to-Modem Flow Control. If the modem-to-line speed is less than the DTE-to-

modem speed, the modem supports XOFF/XON or RTS/CTS flow control with the

DTE to ensure data integrity.

Table 4. +MS Command Automode Connectivity

<mod> Modulation Possible Rates (bps) (1) Notes

V21 V.21 300

V22 V.22 1200

V22B V.22bis 2400 or 1200 Default

V23C V.23 1200 (2)

B103 Bell 103 300

B212 Bell 212 1200

FOOTNOTES:

(1) See optional <automode>, <min_rate>, and <max_rate> subparameters for the +MS command.

(2) For V.23, originating modes transmit at 75 bps and receive at 1200 bps; answering modes transmit at

1200 bps and receive at 75 bps. The rate is always specified as 1200 bps. V.23 half duplex is not

supported.

GENERAL NOTES: If the DTE speed is set to less than the maximum supported DCE speed in

automode, the maximum connection speed is limited to the DTE speed.

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Technical Specifications CX90240 CSM22 Data Sheet

2.3.3 Direct Mode

The Direct mode allows data to be transmitted and received directly from either the

DTE or remote modem. The Direct mode is selected with the AT&Q0 or AT\N1

command.

When running Direct mode, no flow control characters are recognized or transmitted,

and the modem cannot perform error correction. The purpose of the Direct mode is to

make the modem 'dumb' for compatibility with older style modems.

Any data received while the modem is in command mode is lost.

2.3.4 Escape Sequence Detection

The +++ escape sequence can be used to return control to the command mode from

the data mode. Escape sequence detection is disabled by an S2 Register value

greater than 127.

2.3.5 BREAK Detection

The modem can detect a BREAK signal from either the DTE or the remote modem.

The \Kn command determines the modem response to a received BREAK signal.

2.3.6 Telephone Line Monitoring

Loss of Carrier. If carrier is lost for a time greater than specified by the S10 register,

the modem disconnects.

2.3.7 Retrain

The modem may lose synchronization with the received line signal under poor or

changing line conditions. If this occurs, retraining may be initiated to attempt recovery

depending on the type of connection.

The modem initiates a retrain if line quality becomes unacceptable if enabled by the

%E command. The modem continues to retrain until an acceptable connection is

achieved, or until 30 seconds elapse resulting in line disconnect.

2.3.8 Programmable Inactivity Timer

The modem disconnects from the line if data is not sent or received for a specified

length of time. In normal or error-correction mode, this inactivity timer is reset when

data is received from either the DTE or from the line. This timer can be set to a value

between 0 and 255 seconds by using register S30. A value of 0 disables the inactivity

timer.

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CX90240 CSM22 Data Sheet Technical Specifications

2.3.9 DTE Signal Monitoring

DTR#. When DTR# is asserted, the modem responds in accordance with the &Dn and

&Qn commands.

RTS#. R T S# is used for flo w control if enabled by the &K command in n ormal or error-

correction mode.

2.3.10 Call Progress Speaker Interface

A digital speaker output (DSPKOUT) is supported. DSPKOUT is a square wave output

in Data mode used for call progress or carrier monitoring. This output can be optionally

connected to a low-cost on-board speaker, e.g., a sounducer, or to an analog speaker

circuit.

2.3.11 Serial EEPROM Interface

The 20-pin QFN supports a 2-line serial interface to an optional serial EEPROM.

The EEPROM can hold information such as firmware customization, and country code

parameters. Data stored in EEPROM takes precedence over the factory default

settings.

A serial EEPROM is required only if additional storage is required for more country

profiles or customized firmware code.

The EEPROM size can range from 2 Kb (256 x 8) to 256 Kb (32K x 8). A 2 Kb

EEPROM must be 100 kHz or 400 kHz; higher capacity EEPROMs must be 400 kHz.

2.4 Error Correction and Data Compression

2.4.1 V.42 Error Correction

V.42 supports two methods of error correction: LAPM and, as a fallback, MNP 2-4. The

modem provides a detection and negotiation technique for determining and

establishing the best method of error correction between two modems.

2.4.2 MNP 2-4 Error Correction

MNP 2-4 is a data link protocol that uses error correction algorithms to ensure data

integrity. Supporting stream mode, the modem sends data frames in varying lengths

depending on the amount of time between characters coming from the DTE.

2.4.3 V.42 bis Data Compression

V.42 bis data compression mode, enabled by the %Cn or +DS command or S46

compression reporting can be enabled by the +DR and W command.

The V.42 bis data compression employs a “string learning” algorithm in which a string

of characters from the DTE is encoded as a fixed length codeword. Two 512-byte

dictionaries are used to store the strings. These dictionaries are dynamically updated

during normal operation.

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Technical Specifications CX90240 CSM22 Data Sheet

2.5 Telephony Extensions

The following telephony extension features are supported that can typically be

implemented in designs for set-top box applications to enhance end-user experience:

Line In Use detection

Extension Pickup detection

Remote hang-up detection

The -TTE command offers flexibility in tuning the telephony extension features'

sensitivity to accommodate various line conditions.

2.5.1 Line In Use Detection

The Line In Use Detection feature can stop the modem from seizing the phone line

when the line is already being used. When an automated system tries to dial using

ATDT and the phone line is in use, the modem will not go off hook and will respond

with the message “LINE IN USE”.

2.5.2 Extension Pickup Detection

The Extension Pickup Detection feature (also commonly referred as PPD or Parallel

phone detection) allows the modem to detect when another telephony device (i.e., fax

machine, phone, satellite/cable box) is attempting to use the phone line.

This feature can be used to quickly drop a modem connection in the event when a

user picks up a extension phone line. For example, this feature allows set top boxes

with an integrated CX90240 V.22bis Modem to give normal voice users the highest

priority over the telephone line.

2.5.3 Remote Hang-up Detection

The remote hang-up detection feature will cause the modem to go back on-hook and

respond with the message “LINE REVERSAL DETECTED” during a data connection

when the remote modem is disconnected for abnormal termination reasons (remote

phone line unplugged, remote server/modem shutdown).

2.6 Point-of-Sales Support

Point-of-Sales (POS) terminals usually need to exchange a small amount of data in

the shortest amount of time. Low speed modulations such as Bell212A or V.22 are still

mainly used in POS applications. Additionally, new non-standard sequences have

been developed to better support POS applications.

Industry standard and shortened answer tone B103 and V.21 are supported, as well

as FastPOS (V.29) and V.22 FastConnect. POS terminal modulations are supported

by the $F command.

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CX90240 CSM22 Data Sheet Technical Specifications

2.7 Tone Detectors

The modem is equipped with three tone detectors with separate signal paths from the

main received signal path thus enabling tone detection to be independent of the

configuration status.

2.8 Caller ID

Both Type I Caller ID (On-Hook Caller ID) and Type II Caller ID (Call W aiting Caller ID)

are supported for U.S. and many other countries (see Section 2.9). Both types of

Caller ID are enabled/disabled using the +VCID command. When enabled, Caller ID

information (date, time, caller code, and name) ca n be passed to the DTE in formatted

or unformatted form. Inquiry support allows the current Caller ID mode and mode

capabilities of the modem to be retrieved from the modem. Table 5 identifies Caller ID

type differences.

2.8.1 Type II CID

When connected in V.22bis and Call Waiting is detected (assuming Call Waiting

detection is enabled by +PCW = 0 command), the modem notifies the user of

incoming call by toggling the RI pin. Under similar condition except +PCW = 1, the

modem will hang up. In all other modulations, when +PCW = {0 or 1} and Call W aiting

comes in during data mode, the modem will hang up.

When +PCW = 1 and Caller ID is enabled, the modem will attempt to do T ype II Caller

ID before hanging up. The Caller ID information may then be retrieved by issuing

+VRID = {0 or 1} after the modem hangs up.

The modem operates as normal when Call Waiting detection is disabled (+PCW = 2).

However, the modem may also disconnect due to a carrier loss caused by the noise

disturbance that the Call Waiting introduced to the line.

Table 5. Supported Caller ID Types

Caller ID Type Modem State Parallel Phone

Type I CID (On-hook) On-hook On-hook

Type II CID (Call Waiting) Off-hook On-hook

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Technical Specifications CX90240 CSM22 Data Sheet

2.9 Country Support

Internal modem firmware supports 64 country profiles (see Section 1.3.3.2). A country

profile can be uploaded via SRAM patch in addition to, or to override, one of the

default countries in the code. Alternatively, multiple country profiles can also be

uploaded into the external serial NVRAM if supplied by the OEM. Contact the local

Conexant sales office if country code customization is required. These country profiles

include the following country-dependent parameters:

Dial tone detection levels and frequency ranges.

Pulse dialing parameters: make/break times, set/clear times, and dial codes.

Ring detection frequency range.

Type I and Type II Caller ID are supported for many countries. Consult firmware

release notes for a list of the supported countries and the criteria for additional

country support.

Blind dialing enabled/disable.

Calling tone is generated in accordance with V.25. Calling tone may be toggled

(enabled/disabled) by inclusion of a “^” character in a dial string. It may also be

disabled.

Frequency and cadence of tones for busy, ringback, congested, warble, dial tone

1, and dial tone 2.

Answer tone detection period.

Blacklist parameters. The modem can operate in accordance with requirements of

individual countries to prevent misuse of the network by limiting repeated calls to

the same number when previous call attempts have failed. Call failure can be

detected for reasons such as no dial tone, number busy, no answer, no ringback

detected, voice (rather than modem) detected, and key abort (dial attempt aborted

by user). Actions resulting from such failures can include specification of minimum

inter-call delay, extended delay between calls, and maximum numbers of retries

before the number is permanently forbidden (“blacklisted”).

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CX90240 CSM22 Data Sheet Technical Specifications

2.10 Diagnostics

2.10.1 Commanded Tests

Diagnostics are performed in response to &T commands.

Analog Loopback (&T1 Command). Data from the local DTE is sent to the modem,

which loops the data back to the local DTE.

2.11 Low Power Mode

The S24 register sets the length of time, in seconds, that the modem will operate in

normal mode with no detected telephone line or DTE line activity before entering low

power mode. The timer resets upon any DTE line or telephone line activity. Neither

DTE line nor telephone inactivity will cause the modem to enter into low-power mode if

the S24 is set to zero.

When the S24 timer expires, the modem enters into low-power mode, which has four

variations controlled by -SLP or Select Low-Power Mode command. The low-power

mode can be configured either in idle, sleep, deep sleep, or stop mode as shown in

Table 6. Either a ring input or host serial transmit activity will force the modem out of

low-power mode and back to normal mode. Note that the first issued command will get

processed during idle mode but not in sleep or stop mode. The first byte sent merely

wakes up the modem, thus missing the first command. However, subsequent

commands will get processed as normal operating mode resumes.

The device power consumption is listed in Table 6.

Table 6. Select Low-Power Mode (-SLP) Command Comparison Table

AT-SLP = 0 (Idle) 1 (Sleep) 2 (Deep Sleep) 3 (Stop)

Ring input(1) Yes Yes Yes Yes

Host serial TXD activity Yes Yes(2) Yes(2) Yes(2)

FOOTNOTES:

(1) Supported when optional external wake-on-ring is implemented.

(2) The first AT command is ignored but modem returns to normal operating mode.

5/18/12

Technical Specifications CX90240 CSM22 Data Sheet

5/18/12

3Hardware Interface

3.1 CX90240 Modem Hardware Interface Signals

3.1.1 CX90240 Modem Interface Signal Summary

3.1.1.1 LSD Interface (Through DIB)

The DIB interface signals are:

DIBP

DIBN

3.1.1.2 Call Progress Speaker Interface

The call progress speaker interface signal is:

Digital speaker output (DSPKOUT); output

3.1.1.3 Clock Select Interface

The clock select interface signal is:

Clock Select (CLKSEL); input

3.1.1.4 Serial EEPROM Interface

The 2-line serial interface signals to an optional serial EEPROM are:

Bidirectional Data input/output (NVMDATA)

Clock output (NVMCLK)

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Hardware Interface CX90240 CSM22 Data Sheet

3.1.1.5 Serial DTE Interface and Indicator Outputs

The supported DTE interface signals are:

Serial Transmit Data input (TXD#)

Serial Receive Data output line (RXD#)

Clear to Send output (CTS#)

Received Line Signal Detector output (RLSD#)

Ring Indicator output (RI#)

Data Terminal Ready control input (DTR#)

Request to Send control input (RTS#)

Data Set Ready output (DSR#)

3.1.1.6 Control Signals

The supported control signals are:

Reset (RESET#); input

Low Power Oscillator Select (LPO); input

3.1.1.7 Crystal/Clock and Power Signals

Supported crystal and power signals are:

Crystal/Clock input (XTLI)

Crystal return (XTLO)

+3.3 V power (VDD)

Ground (VSS)

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CX90240 CSM22 Data Sheet Hardware Interface

3.1.2 CX90240 Modem Pin Assignments and Signal Definitions

CX90240 Modem hardware interface signals are shown by major interface in Figure 2,

are shown by pin number in Figure 3, and are listed by pin number in Table 7.

CX90240 Modem hardware interface signals are defined in Table 8.

Figure 2. CX90240 Modem Hardware Interface Signals

Figure 3. CX90240 Modem 20-Pin QFN Pin Signals

XTLI

XTLO

TXD#

RXD#

CTS#

RLSD#

RI#

DTR#

RTS#

NVMCLK/CLKSEL

NVMDATA

RESET#

LPO

SERIAL HOST

INTERFACE

DIBN

DIBP

DSPKOUT

VDD_CORE

VDD

GND

PADDLE (GND)

CX90240

Modem

20-Pin QFN

DIGITAL ISOLATION

BARRIER (DIB)

RESET CIRCUIT

SPEAKER CIRCUIT

+3.3V

240K

+3.3V

28.224 OR 27.000 MHZ

CRYSTAL OR CLOCK OSCILLATOR

FREQUENCY SELECT CIRCUIT

SERAIL EEPROM

+1.8V DECOUPLING

GENERAL NOTE: PADDLE (GND), indicated as Pin 21, is a conductive surface on the bottom of the device and must be connected to system side

digital ground.

CX90240

VDD_CORE

LPO

VDD

NVMDATA

DIBP

RXD#

TXD#

VDD

NVMCLK/CLKSEL

RTS#

CTS#

DTR#

RLSD#

RI#

DIBN

RESET#

XTLO

XTLI

DSPKOUT

GND

GENERAL NOTE: PADDLE (GND) is a conductive surface on the bottom of the PADDLE (GND) is a

conductive surface on the bottom of the device and is indicated as pin 21.

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

Table 7. CX90240 Modem 20-Pin QFN Pin Signals

Pin Number Signal Name Pin Number Signal Name

1RXD# 11DIBP

2 TXD# 12 NVMDATA

3VDD 13VDD

4 NVMCLK/CLKSEL 14 LPO

5RTS# 15VDD_CORE

6CTS# 16GND

7 DTR# 17 DSPKOUT

8 RLSD# 18 XTLI

9 RI# 19 XTLO

10 DIBN 20 RESET#

21 PADDLE (GND)

GENERAL NOTES: PADDLE (GND) is a conductive surface on the bottom of the device and is indicated

as pin 21.

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

Table 8. CX90240 Modem Hardware Signal Definitions (1 of 3)

Label Pin I/O I/O Type Signal Name/Description

System

XTLI

XTLO 18

19 I

OIx

Ox Crystal In and Crystal Out. If an external 27 or 28.224 MHz crystal circuit is

used instead of an external clock circuit, connect XTLI and XTLO to the

external crystal circuit. When an external clock circuit is used, connect the

clock signal to XTLI and leave XTLO open. (See CLKSEL pin description.)

NVMCLK/CLKSEL 4 I Ipu/O2 Clock Frequency Select (CLKSEL). Clock frequency is selected by CLKSEL

during reset processing. Leave open for 28.224 MHz operation; connect pin to

digital ground (GND) for 27.000 MHz operation.

This signal is multiplexed with NVMCLK.

RESET# 20 I Ipu/O2 Reset. The active low RESET# input resets the modem logic and clears the

internal SRAM.

RESET# low holds the modem in the reset state; RESET# going high releases

the modem from the reset state. After application of VDD, RESET# must be

held low for at least 15 ms after the VDD power reaches operating range. The

modem device set is ready to use 25 ms after the low-to-high transition of

RESET#.

VDD_CORE 15 O PWR +1.8 V Internal Core Voltage Filter. Internal +1.8 V core voltage for

decoupling. Do not connect this pin to an external +1.8 V power supply.

VDD 3, 13 O PWR Digital and I/O Circuits Supply Voltage. Connect this pin to an external +3.3

V power supply.

GND 16 I GND Digital Ground. Connect to digital ground (GND).

PADDLE (GND) 21 G GND Paddle Ground. Connect to digital ground (GND).

LPO 14 I Low Power Oscillator. Connect to +3.3V through 240 kΩ.

Speaker Interface

DSPKOUT 17 O Ipd/O2 Modem Speaker Digital Output. The DSPKOUT digital output reflects the

received analog input signal digitized to TTL high or low level by an internal

comparator.

DIB Interface

DIBN 10 O Odpc DIB Negative. Provides clock and power to the LSD, and transfers data,

control and status information between the SSD and LSD. Connect to DIB

transformer primary winding terminal.

DIBP 11 O Odpc DIB Positive. Provides clock and power to the LSD and transfers data, control

and status information between the SSD and LSD. Connect to DIB transformer

primary winding terminal.

NVRAM Interface

NVMCLK/CLKSEL 4 I/O Ipu/O2 NVRAM Clock (NVMCLK). During normal operation, NVMCLK/CLKSEL

output high enables the EEPROM. Connect to EEPROM SCL pin.

This signal is multiplexed with CLKSEL.

NVMDATA 12 I/O Ipu/O2 NVRAM Data. The NVMDATA pin supplies a serial data interface to the

EEPROM. Connect to EEPROM SDA pin and to +3.3V through 10 kΩ.

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

V.24 (EIA/TIA-232-E) DTE Serial Interface

TXD# 2 I Ipu/O2 Transmit Serial Input (EIA BA/ITU-T CT103). Serial data is sent on this line

from the DTE to the DCE. The DTE holds this line at logic 1 when no data is

being transmitted. The following signals must be at logic 0, where

implemented, before data can be transmitted on this line: Request To Send

(RTS), Clear To Send (CTS), and Data Terminal Ready (DTR).

RXD# 1 O Ipu/O2 Receive Serial Output (EIA BB/ITU-T CT104). Serial data is sent on this line

from the DCE to the DTE. This pin is held at logic 1 (Mark) when no data is

being transmitted, and is held logic 1 for a brief interval after a logic 0 to 1

transition on the Request To Send line (RTS), in order to allow the transmission

to complete.

CTS# 6 O Ipu/O2 Clear To Send (EIA CB/ITU-T CT106). An answer signal to the DTE. When

this signal is active, it tells the DTE that it can now start transmitting. When

CTS is logic 0 and the Request To Send (RTS) and Data Terminal Ready

(DTR) are both logic 0, the DTE is assured that its data will be sent to the

communications link. Logic 1 indicates to the DTE that the DCE is not ready,

and therefore data should not be sent.

In asynchronous operation, in error correction or normal mode, CTS is always

at logic 0 unless RTS/CTS flow control is selected by the &Kn command.

In synchronous operation, the modem also holds CTS at logic 0 during

asynchronous command state. The modem switches CTS to logic 1

immediately upon going off-hook and holds it there until RLSD is at logic 0 in

which case the modem is ready to transmit and receive synchronous data. CTS

can also track the state of RTS via the &Rn command.

RLSD# 8 O Ipu/O2 Received Line Signal Detector (EIA CF/ITU-T CT109). The DCE uses this

line to signal the DTE that a good signal is being received assuming AT&C0

command is not in effect (a “good signal” means a good analog carrier , that can

ensure demodulation of received data).

RI# 9 O Ipu/O2 Ring Indicator (EIA CE/ITU-T CT125). On this line the DCE signals the DTE

that there is an incoming call. This signal is maintained at logic 1 at all times

except when the DCE receives a ringing signal.

DTR# 7 I Ipu/O2 Data Terminal Ready (EIA CD/ITU-T CT108). The DTR# input is turned ON

(low) by the DTE when the DTE is ready to transmit or receive data. DTR# ON

prepares the modem to be connected to the telephone line, and maintains the

connection established by the DTE (manual answering) or internally (automatic

answering). DTR# OFF places the modem in the disconnect state under

control of the &Dn and &Qn commands.

Table 8. CX90240 Modem Hardware Signal Definitions (2 of 3)

Label Pin I/O I/O Type Signal Name/Description

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

3.1.3 CX90240 Modem Electrical Characteristics

CX90240 I/O types are defined in Table 9.

CX90240 DC electrical characteristics are listed in Table 10.

RTS# 5 I Ipu/O2 Request To Send (EIA CA/ITU-T CT105). The DTE uses this signal when it

wants to transmit to the DCE. This signal, in combination with the Clear To

Send (CTS) signal, coordinates data transmission between the DTE and the

DCE.

A logic 0 on this line keeps the DCE in transmit mode. The DCE will receive

data from the DTE to be forwarded to the communication link.

The RTS and CTS signals relate to a half-duplex telephone line. A half duplex

line is capable of carrying signals on both directions but only one at a time.

When the DTE has data to send, it raises RTS, and then waits until the DCE

changes from receive to transmit mode. The logic 1 to 0 transition of the RTS

instructs the DCE to switch to “transmit” mode, and when a transmission is

possible, the DCE sets CTS and transmission can begin.

On a full duplex line, like a hard-wired connection, where transmission and

reception can occur simultaneously, the CTS and RTS signals are held to a

constant logic 0 level. A logic 0 to 1 transition of the RTS instructs the DCE to

complete data transmission and to switch to a “receive” (or “no transmission”)

mode.

Table 9. CX90240 Modem I/O Type Definitions

I/O Type Description

Idd/Odd Digital input/output, DIB data transceiver

Ix/Ox I/O, wire

Ipd/O2 Digital input, 120 kΩ pull-down / Digital output, 2 mA

Ipu/O2 Digital input, 120 kΩ pull-up / Digital output, 2 mA

Ippu/O2 Digital input, Programmable 120 kΩ pull-up / Digital output, 2 mA

Odpc Digital output with adjustable drive, DIB clock and power

Rx Oscillator Pad, place 120 kΩ resistor from pad to VDD

PWR Power

GND Ground

GENERAL NOTES:

1. See DC characteristics in Table 10.

2. I/O Type corresponds to the device Pad Type. The I/O column in signal interface tables refers to signal I/O direction used in the

application.

Table 8. CX90240 Modem Hardware Signal Definitions (3 of 3)

Label Pin I/O I/O Type Signal Name/Description

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

Table 10. CX90240 Modem DC Electrical Characteristics

Parameter Symbol Minimum Maximum Units Test Conditions

Input Voltage Low VIL 0 0.3 *VDD V

Input Voltage High VIH 0.7 * VDD VDD V

Input Current (no Pull-Down or

Pull-Up) IIL -1 +1 uA OEN = 1

Input Current (Pull-Down) IPD +6 +30 uA VIN = VDD

Input Current (Pull-Up) IPU -300 -60 uA VIN = GND

Output Voltage Low VOL 0 0.4 V IOL = +2 mA

Output Voltage High VOH VDD-0.4 VDD V IOL = -2 mA

Output Impedance Z 25 95 W

Pull-Up Resistance Rpu 120 500 kΩVIN = GND

Pull-Down Resistance Rpd 120 500 kΩVIN = VDD

GENERAL NOTES: Test Conditions unless otherwise stated: VDD = +3.3V ± 5%; TA = 0°C to 70°C; external load = 50 pF.

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

3.2 CX20548 LSD Hardware Pins and Signals

3.2.1 General

3.2.1.1 Host Side Device (HSD) Interface (Through DIB)

The DIB interface signals are:

DIB Positive (DIBP, pin 14); input/output

DIB Negative (DIBN, pin 16); input/output

3.2.1.2 Power and Ground

The power and ground signals are:

Unregulated Power Output (PWR, pin 15)

Regulated Digital Power Output (DVDD, pin 1)

Regulated Analog Power Output (AVDD, pin 2)

Analog Ground (PADDLE [AGND]); Analog ground

3.2.1.3 Telephone Line Interface

The telephone line interface signals are:

RING AC Coupled (RAC, pin 4); input

TIP AC Coupled (TAC, pin 5); input

Electronic Inductor Capacitor (EIC, pin 11)

Electronic Inductor Output (EIO, pin 10)

Electronic Inductor Feedback (EIF, pin 9)

Receive Analog Input (RXI, pin 6); input

Transmit Output (TXO, pin 8); output

Transmit Feedback (TXF, pin 7); input

3.2.1.4 Voltage References

There is on reference voltage pin:

Output Middle (Center) Reference Voltage (VC, pin 3); output for decoupling

3.2.1.5 General Purpose Input/Output

There is one unassigned general purpose input/output pin:

General Purpose Input/Output (GPIO, pin 13); input/output

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

3.2.2 Pin Assignments and Signal Definitions

CX20548 LSD hardware interface signals are shown by major interface in Figure 4,

are shown by pin number in Figure 5, and are listed by pin number in Table 11.

CX20548 LSD hardware interface signals are defined in Table 12.

CX20548 LSD GPIO DC characteristics are specified in Table 13.

CX20548 LSD AVDD DC characteristics are specified in Table 14.

Figure 4. CX20548 LSD Hardware Interface Signals

NOTE: Pin 17 is shown in Figure 4 to ensure that the PADDLE is considered

when laying out the printed circuit board. The PADDLE is the analog

ground pin of the CX20548 device and must be connected to LSD

analog ground (AGND_LSD) when the CX20548 is populated in a PCB.

RAC

TAC

EIC

EIO

EIF

RXI

TXO

TXF

GPIO

CX20548

SmartDAA 4

Line Side

Device

(LSD)

16-Pin QFN

Electronic

Inductor, Off-

Hook, Pulse

Dial, and TIP

and RING VI

Control

AGND_LSD

Safety

and EMI

Protection

AGND_LSD

C844

Receive

Coupling

Impedance

Matching

and

Transmitter

DIBN

DIBP

TEST

DVDD

PWR+

AVDD

PADDLE (AGND)

C828

AGND_LSD

DIGITAL

ISOLATION

BARRIER

(DIB)

DIBN

DIBP

Telephone

Line

Connector

TIP

RING

C852

C850

GENERAL NOTES:

1. Consult applicable reference design for exact component placement and values, and for layout guidelines.

2. The PADDLE (indicated as Pin 17) is the analog ground pin of the CX20548 device and must be connected to LSD analog ground (AGND_LSD)

when the CX20548 is populated in a printed circuit board (PCB).

C862

C870

AGND_LSD

R802

R804

R854

AGND_LSD

C830

T802

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

Figure 5. CX20548 LSD 16-Pin QFN Pin Signals

Table 11. CX20548 LSD 16-Pin QFN Pin Signals

Pin Signal Label Pin Signal Label

1DVDD 9EIF

2AVDD 10 EIO

3VC 11 EIC

4RAC 12 TEST

5TAC 13 GPIO

6RXI 14 DIBP

7TXF 15 PWR

8TXO 16 DIBN

17 PADDLE (AGND)

CX20548

DVDD

AVDD

RAC

TAC

RXI

TXF

TXO

TEST

EIC

EIO

EIF

DIBN

PWR

DIBP

GPIO

GENERAL NOTE: The PADDLE, a connective surface located on the bottom of the package and referred

to as pin 17, is connected internally to analog ground (AGND).

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

Table 12. CX20548 LSD Hardware Signal Definitions (1 of 2)

Label Pin I/O I/O Type Signal Name/Description

System Interface Signals

PWR 15 PWR PWR Unregulated Power Output. Unregulated power output from the internal

rectifier, connect to AGND_LSD through C870.

VC 3 REF REF Output Middle Reference Voltage. Connect to AGND_LSD through C844,

which must be placed close to pin 3. Use a short path and a wide trace to

AGND_LSD pin.

AVDD 2 PWR PWR Analog Power Output. Provides external connection point for decoupling.

(AVDD is routed internally to LSD analog circuits.). Connect to

AGND_LSD through C828. C828 must be placed close to pins 2.

DVDD 1 PWR PWR Digital Power Output. Provides external connection point for decoupling.

Connect to AGND_LSD through C830. Place C830 near pin 1.

PADDLE

(AGND) 17 AGND_LSD AGND_LSD Paddle Analog Ground. The conductive surface located on the bottom of the

package and referred to as pin 17 is connected internally to device analog

ground. Connect to AGND_LSD.

DIB Interface Signals

DIBP 14 I/O I/O DIB Positive. Positive terminal of DIB, connect to secondary of DIB transformer.

DIBN 16 I/O I/O DIB Negative. Negative terminal of DIB, connect to secondary of DIB

transformer.

TIP and RING Interface Signals

RAC

TAC 4

IIa

aRING AC Coupled and TIP AC Coupled. Un-rectif ied vol tage from telephone

line used to detect ring.

Connect RAC to the diode bridge AC node (RING) through R802 (connects to

pin 4).

Connect TAC to the diode bridge AC node (TIP) through R804 (connects to pin

5).

EIC 11 O Oa Electronic Inductor Capacitor. Electronic inductor filtering capacitor. Connect

to AGND_LSD through C858.

EIO 10 O Oa Electronic Inductor Output. Calculated voltage is applied to this output to

control off-hook and DC VI mask operation. Connect to base of Q804.

EIF 9 I Ia Electronic Inductor Feedback. Connect to emitter of Q804 through R826.

RXI 6 I Ia Receive Analog Input. Receiver operational amplifier inverting input. AC

coupled to the Bridge_CC node through R810 (connects to pin 6) and C810 in

series. R810 and C810 must be placed very close to pin 6. The length of the

PCB trace connecting R810 to the RXI pin must be kept at an absolute

minimum.

TXO 8 O Oa Transmit Output. Outputs transmit sig nal and impedan ce matc hin g signa l;

connect to base of transistor Q802.

TXF 7 I Ia Transmit Feedback. Connect to emitter of transistor Q802.

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

Not Used

GPIO 1 I/O It/Ot12 General Purpose I/O. Leave open if not used.

GENERAL NOTES:

1. I/O types*:

IaAnalog input

ItDigital input*

OaAnalog output

Ot12Digital output*

AGND_LSDIsolated LSD Analog Ground (isolated from the host system ground)

*See Section CX20548 LSD GPIO DC Electrical Characteristics ().

2. Refer to applicable reference design for exact component placement and values.

Table 13. CX20548 LSD GPIO DC Electrical Characteristics

Parameter Symbol Minimum Typical Maximum Units Test Conditions

Input Voltage VIN -0.30 – 3.465 V DVDD = +3.465V

Input Voltage Low VIL ––1.0V

Input Voltage High VIH 1.6––V

Output Voltage Low VOL 0–0.33V

Output Voltage High VOH 2.97––V

Input Leakage Current – -10 – 10 µA

Output Leakage Current (High Impedance) – -10 – 10 µA

GPIO Output Sink Current at 0.33 V maximum – 2.4 – - mA

GPIO Output Source Current at 2.97 V minimum – 2.4 – - mA

GPIO Rise Time/Fall Time 20 100 ns

GENERAL NOTES: Test Conditions unless otherwise stated: DVDD = +3.3V +5%; TA = 0°C to 70°C; external load = 50 pF

Table 14. CX20548 LSD AVDD and DVDD DC Electrical Characteristics

PWR Input AVDD Output DVDD Output

+3.3 V < PWR < +4.5 V +3.3 V ± 5% +3.0 V ± 5%

GENERAL NOTES: PWR must be at least 100 mV higher than AVDD. See PWR,

AVDD, and DVDD descriptions in.

Table 12. CX20548 LSD Hardware Signal Definitions (2 of 2)

Label Pin I/O I/O Type Signal Name/Description

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

3.3 Operating Conditions, Absolute Maximum Ratings, and

Power Requirements

The CX90240 operating conditions are specified in Table 15.

The CX90240 absolute maximum ratings are listed in Table 16.

The CX90240 current and power requirements are listed in Table 17.

Table 15. CX90240 Modem Operating Conditions

Parameter Symbol Limits Units

Supply Voltage VDD +3.3 ± 5% VDC

Operating Ambient Temperature TA0 to +70 °C

Note: Voltages referenced to ground (VSS).

Table 16. Absolute Maximum Ratings

Parameter Symbol Limits Units

Common

Storage Tem perat ure Range TSTG -55 to +125 °C

Relative humidity HREL Up to 90% non-condensing, or a wet

bulb temperature up to 35 °C,

whichever is less.

CX90240 Modem

VDD Supply Voltage VDD -0.5 to +4.0 VDC

Input Voltage VIN -0.3 to (VDD + 0.3) VDC

Voltage Applied to Outputs in High Impedance (Off) State VHZ -0.5 to +5.5 VDC

DC Input Clamp Current IIK ±20 mA

DC Output Clamp Curre nt IOK ±20 mA

Static Discharge Volta ge (2 5°C) VESD ±2500 VDC

Latch-up Current (25°C) ITRIG ±400 mA

5/18/12

CX90240 CSM22 Data Sheet Hardware Interface

3.3.1 Handling CMOS Devices

The device contains circuitry to protect the inputs against damage due to high static

voltages. However, it is advised that normal precautions be taken to avoid application

of any voltage higher than maximum rated voltage.

An unterminated input can acquire unpredictable voltages through coupling with stray

capacitan ce and internal cross talk. Both power dissip ation and device noise immunity

degrades. Therefore, all inputs should be connected to an appropriate supply voltage.

Input signals should never exceed the voltage range from -0.3V to (VDD + 0.3) V. This

prevents forward biasing the input protection diodes and possibly entering a latch up

mode due to high current transients.

Table 17. Current and Power Requirements

Mode Typical Current

(Ityp)

(mA)

Maximum Current

(Imax)

(mA)

Typical Power

(Ptyp)

(mW)

Maximum Power

(Pmax)

(mW)

Normal Mode: Off-hook, normal data connection 61.1 69.1 201.8 248.7

Normal Mode: On-hook, idle, waiting for ring 48.5 55.6 160.1 200.0

Normal Mode: Connected (no compression) 60.7 68.6 200.4 247.1

Normal Mode: Connected (compression enabled) 60.7 68.6 200.1 247.1

Low-Power Mode: Idle (-slp = 0) 6.0 7.2 19.8 26.0

Low-Power Mode: Sleep (-slp = 1) 6.0 7.2 19.8 26.0

Low-Power Mode: Deep Sleep (-slp = 2) 5.1 6.1 16.7 21.8

Low-Power Mode: Stop (-slp = 3) 4.0 5.2 13.2 18.6

GENERAL NOTES:

1. Operating voltage: VDD = +3.3 V ± 5%.

2. Test conditions: VDD = +3.3 V for typical values; VDD = +3.6 V for maximum values.

3. Input Ripple ≤ 0.1 Vpeak-peak.

4. Typical power (Ptyp) computed from Ityp: Ptyp = Ityp * 3.3 V;

Maximum power (Pmax) computed from Imax: Pmax = Imax * 3.6 V.

5/18/12

Hardware Interface CX90240 CSM22 Data Sheet

3.4 Crystal and Clock Specifications

Crystal specifications are listed in Table 18. Clock specifications are listed in Table 19.

Table 18. Crystal Specifications

Characteristic Value

Frequency 28.224 or 27.000 MHz nominal

Calibration Tolerance ±50 ppm at 25°C (CL = 16.5 and 19.5 pF)

Frequency Stability vs. Temperature ±35 ppm (0°C to 70°C)

Frequency Stability vs. Aging ±20 ppm/5 years

Oscillation Mode Fundamental

Calibration Mode Parallel resonant

Load Capacitance, CL18 pF nom.

Shunt Capacitance, CO7 pF max.

Series Resistance, R1 35-60 Ω max. @20 nW drive level

Drive Level 100 µW correlation; 500 µW max.

Operating Temperature 0°C to 70°C

Storage Temperature –40°C to 85°C

Table 19. Clock Specifications

Characteristic Value

Type Square wave

Frequency 28.224 or 27.000 MHz nominal

Level 3.3 Vp-p ± 0.3 V ze ro offset

Duty Cycle 50 ± 10%

Stability ±50 ppm

5/18/12

4Package Dimensions

The CX90240 comes in a 20-pin package in either punch or sawn style. Both are

electrically equivalent and share the same footprint. Table 20 provides a dimension

table that is common to both QFN styles. The punch-style package is shown in

Figure 6, and the sawn-style package is shown in Figure 7.

Table 20. Package Dimensions for 20-Pin QFN Punch and Sawn Styles

Dim. mm Note

Min. Nom. Max.

e 0.8 BSC

L0.5 0.75

b 0.28 0.4

D2 3.95 4.25

E2 3.95 4.25

A0.8 0.90

A1 0.00 0.05

A3 0.20 REF.

D 6.00 BSC

D1 5.75 BSC (1)

E 6.00 BSC

E1 5.75 BSC (1)

GENERAL NOTES:

1. All dimensions in mm.

2. Shape of Pin #1 indicator on the bottom of package can be different (i.e., Chamfer, Half Circle).

FOOTNOTES:

(1) This dimension is applied only for Punched QFN.

5/18/12

Package Dimensions CX90240 CSM22 Data Sheet

Figure 6. Package Dimensions for 20-Pin QFN, Punch Style

5/18/12

CX90240 CSM22 Data Sheet Package Dimensions

Figure 7. Package Dimensions for 20-Pin QFN, Sawn Style

5/18/12

Package Dimensions CX90240 CSM22 Data Sheet

The CX20548 comes in a 16-pin QFN package, in either punch or sawn style. Both are

electrically equivalent and share the same footprint. Table 21 provides a dimension

table that is common to both QFN styles. The punch-style package is shown in

Figure 8, and the sawn-style package is shown in Figure 9.

Table 21. Package Dimensions for 16-Pin QFN Punch and Sawn Styles

Dim. Minimum Nominal Maximum Note

e 0.65 BSC

L0.5 0.75

b0.21 0.35(1)

D2 1.95 2.10 2.25

E2 1.95 2.10 2.25

A0.8 1.00

A1 0.00 0.05

A3 0.20 REF.

D 4.00 BSC

D1 3.75 BSC (2)

E 4.00 BSC

E1 3.75 BSC (2)

GENERAL NOTES:

1. All dimensions in mm.

2. Shape of Pin #1 indicator on the bottom of package can be different (i.e., Chamfer or

Half Circle).

FOOTNOTES:

(1) Dimension b applies to plated terminal and is measured between 0.20 and 0.30 mm

from terminal tip.

(2) This dimension is applied only for Punched QFN.

5/18/12

CX90240 CSM22 Data Sheet Package Dimensions

Figure 8. CX20548 16-Pin QFN, Punch Style

NOTE 1

SCALE: NONE

SECTION "C-C"

TERMINAL TIP

TOP VIEW

Pin 1

Identifier

BOTTOM VIEW

PLANE

SEATING

16 Pin 1

Identifier

SIDE VIEW

5/18/12

Package Dimensions CX90240 CSM22 Data Sheet

Figure 9. CX20548 16-Pin QFN, Sawn Style

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