844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
1
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
GENERAL DESCRIPTION
The ICS844051I is a Gigabit Ethernet Clock
Generator and a member of the HiPerClocksTM
family of high performance devices from ICS.
The ICS844051I can synthesize 10 Gigabit
Ethernet, SONET, or Serial ATA reference clock
frequencies with the appropriate choice of crystal and output
divider. The ICS844051I has excellent phase jitter perfor-
mance and is packaged in a small 8-pin TSSOP, making it
ideal for use in systems with limited board space.
FEATURES
•One Differential LVDS output
•Crystal oscillator interface designed for
18pF parallel resonant crystals (18.125MHz - 23.4375MHz)
•Output frequency range: 145MHz - 187.5MHz and
72.5MHz - 93.75MHz
•VCO range: 580MHz - 750MHz
•RMS phase jitter @156.25MHz (1.875MHz - 20MHz):
0.45ps (typical)
•3.3V or 2.5V operating supply
•-40°C to 85°C ambient operating temperature
•Available in both standard and lead-free RoHS-compliant
packages
HiPerClockS™
ICS
ICS844051I
8-Lead TSSOP
4.40mm x 3.0mm x 0.925mm
package body
G Package
Top View
VDDA
GND
XTAL_OUT
XTAL_IN
1
2
3
4
VDD
Q
nQ
FREQ_SEL
8
7
6
5
BLOCK DIAGRAM
OSC Phase
Detector VCO
0 ÷4 (default)
1 ÷8
÷32
(fixed)
XTAL_IN
XTAL_OUT
Q
nQ
FREQUENCY TABLE
PIN ASSIGNMENT
FREQ_SEL
stupnI ycneuqerFtuptuO
)zHM(
)zHM(ycneuqerFlatsyrCLES_QERF
106141.020218231.161
106141.021604665.08
52135.91052.65
1
52135.911521.87
44.91025.551
44.91167.77
57.810051
57.81157
Pulldown
The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on
initial product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications
without notice.
DATA SHEET
ICS844051I
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
1
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK
GENERATOR
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
2
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
TABLE 2. PIN CHARACTERISTICS
TABLE 1. PIN DESCRIPTIONS
rebmuNemaNepyTnoitpircseD
1V
ADD
rewoP.nipylppusgolanA
2DNGrewoP.dnuorgylppusrewoP
4,3 ,TUO_LATX
NI_LATX tupnI ,tupniehtsiNI_LATX.ecafretnirotal
licsolatsyrC
.tuptuoehtsiTUO_LATX
5LES_QERFtupnIpulluP.niptcelesycneuqerF
7,6Q,QntuptuO.slevelecafretniSDVL.stu
ptuokcolclaitnereffiD
8V
DD
rewoP.nipylppusrewoP
:ETON pulluP .seulavlacipytrof,scitsiretcarahCniP,2elbaTeeS.srotsisertupnilanretniot
srefer
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
C
NI
ecnaticapaCtupnI 4Fp
R
PULLUP
rotsiseRpulluPtupnI 15kΩ
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
2
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
3
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
TABLE 3A. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDA = 3.3V±5%, TA = -40°C TO 85°C
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
DD 4.6V
Inputs, VI-0.5V to VDD + 0.5 V
Outputs, IO (LVDS)
Continuous Current 10mA
Surge Current 15mA
Package Thermal Impedance, θJA 101.7°C/W (0 mps)
Storage Temperature, T
STG -65°C to 150°C
NOTE: Stresses beyond those listed under Absolute
Maximum Ratings may cause permanent damage to the
device. These ratings are stress specifications only. Functional
operation of product at these conditions or any conditions be-
yond those listed in the DC Characteristics or AC Character-
istics is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect product reliability.
TABLE 3C. LVCMOS/LVTTL DC CHARACTERISTICS, VDD = VDDA = 3.3V±5% OR 2.5V±5%, TA = -40°C TO 85°C
TABLE 3B. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, TA = -40°C TO 85°C
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
V
DD
egatloVylppuSrewoP 531.33.3564.3V
V
ADD
egatloVylppuSgolanA 531.33.3564.3V
I
DD
tnerruCylppuSrewoP 001Am
I
ADD
tnerruCylppuSgolanA 8Am
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
V
DD
egatloVylppuSrewoP 573.25.2526.2V
V
ADD
egatloVylppuSgolanA 573.25.2526.2V
I
DD
tnerruCylppuSrewoP 59Am
I
ADD
tnerruCylppuSgolanA 8Am
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
V
HI
egatloVhgiHtupnI V
DD
V3.3=2V
DD
3.0+V
V
DD
5.2=7.1V
DD
3.0+V
V
LI
egatloVwoLtupnI V
DD
V3.3=3.0-8.0V
V
DD
5.2=3.0-7.0V
I
HI
tnerruChgiHtupnIV
DD
V=
NI
V526.2roV564.3=5Aµ
I
LI
tnerruCwoLtupnIV
DD
V,V526.2roV564.3=
NI
V0=051-Aµ
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
3
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
4
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
TABLE 4. CRYSTAL CHARACTERISTICS
TABLE 5A. AC CHARACTERISTICS, VDD = VDDA = 3.3V±5%, TA = -40°C TO 85°C
TABLE 5B. AC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, TA = -40°C TO 85°C
TABLE 3E. LVDS DC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, TA = -40°C TO 85°C
TABLE 3D. LVDS DC CHARACTERISTICS, VDD = VDDA = 3.3V±5%, TA = -40°C TO 85°C
retemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
noitallicsOfoedoM latnemadnuF
ycneuqerF 521.815734.32zHM
)RSE(e
cnatsiseRseireStnelaviuqE 05 Ω
ecnaticapaCtnuhS 7Fp
leveLevirD 1Wm
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
V
DO
egatloVtuptuOlaitnereffiD 053Vm
ΔV
DO
V
DO
egnahCedutingaM 004Vm
V
SO
egatloVtesffO 4.1V
ΔV
SO
V
SO
egnahCedutingaM 05Vm
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
V
DO
egatloVtuptuOlaitnereffiD 053Vm
ΔV
DO
V
DO
egnahCedutingaM 004Vm
V
SO
egatloVtesffO 51.1V
ΔV
SO
V
SO
egnahCedutingaM 04Vm
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
f
TUO
ycneuqerFtuptuO 52.651zHM
t)Ø(tij ;)modnaR(rettiJesahPSMR
1ETON
:egnaRnoitargetnI@zHM52.651
zHM02-zHM578.1 54
.0sp
t
R
t/
F
emiTllaF/esiRtuptuO%08ot%02003sp
cdoelcyCytuDtuptuO 05%
.noitcessihtgniwollofstolPesioNesahPehtotreferesaelP:
1ETON
lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU
f
TUO
ycneuqerFtuptuO 52.651zHM
t)Ø(tij ;)modnaR(rettiJesahPSMR
1ETON
:egnaRnoitargetnI@zHM52.651
zHM02-zHM578.1 54
.0sp
t
R
t/
F
emiTllaF/esiRtuptuO%08ot%02003sp
cdoelcyCytuDtuptuO 05%
.noitcessihtgniwollofstolPesioNesahPehtotreferesaelP:
1ETON
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
4
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
5
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
100 1k 10k 100k 1M 10M 100M
100 1k 10k 100k 1M 10M 100M
TYPICAL PHASE NOISE AT 156.25MHZ @ 3.3V
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
-150
-160
-170
-180
-190
156.25MHz
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.45ps (typical)
OFFSET FREQUENCY (HZ)
NOISE POWER dBc
Hz
Phase Noise Result by adding
Gb Ethernet Filter to raw data
Raw Phase Noise Data
Gb Ethernet Filter
➤
156.25MHz
RMS Phase Jitter (Random)
1.875MHz to 20MHz = 0.45ps (typical)
OFFSET FREQUENCY (HZ)
NOISE POWER dBc
Hz
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
-150
-160
-170
-180
-190
Phase Noise Result by adding
Gb Ethernet Filter to raw data
Raw Phase Noise Data
Gb Ethernet Filter
TYPICAL PHASE NOISE AT 156.25MHZ @ 2.5V
➤
➤
➤
➤
➤
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
5
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
6
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
PARAMETER MEASUREMENT INFORMATION
OUTPUT RISE/FALL TIME OFFSET VOLTAGE SETUP
LVDS 3.3V OUTPUT LOAD AC TEST CIRCUIT LVDS 2.5V OUTPUT LOAD AC TEST CIRCUIT
RMS PHASE JITTER OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
SCOPE
Qx
nQx
LVDS
Power Supply
+-
Float GND
Q
nQ
➤
➤
➤
100
out
out
LVDS
DC Input VOD/Δ VOD
VDD
out
out
LVDS
DC Input
➤
➤
➤
V
OS
/Δ V
OS
V
DD
VDD
VDD
Clock
Outputs 20%
80% 80%
20%
t
R
t
F
V
SWING
DIFFERENTIAL OUTPUT VOLTAGE SETUP
SCOPE
Qx
nQx
LVDS
2.5V±5%
POWER SUPPLY
+-
Float GND
Phase Noise Mas
k
Offset Frequency
f
1
f
2
Phase Noise Plot
RMS Jitter = Area Under the Masked Phase Noise Plot
Noise Power
t
PW
tPERIOD
t
PW
t
PERIOD
odc = x 100%
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
6
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
7
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
APPLICATION INFORMATION
Figure 2. CRYSTAL INPUt INTERFACE
CRYSTAL INPUT INTERFACE
The ICS844051I has been characterized with 18pF parallel
resonant crystals. The capacitor values, C1 and C2, shown in
Figure 2 below were determined using a 25MHz, 18pF parallel
resonant crystal and were chosen to minimize the ppm error.
The optimum C1 and C2 values can be slightly adjusted for dif-
ferent board layouts.
POWER SUPPLY FILTERING T ECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS844051I provides
separate power supplies to isolate any high switching
noise from the outputs to the internal PLL. VDD and VDDA should
be individually connected to the power supply
plane through vias, and bypass capacitors should be
used for each pin. To achieve optimum jitter performance,
power supply isolation is required. Figure 1 illustrates how
a 10Ω resistor along with a 10μF and a .01μF bypass
capacitor should be connected to each VDDA pin. The 10Ω
resistor can also be replaced by a ferrite bead. FIGURE 1. POWER SUPPLY FILTERING
10Ω
VDDA
10μF
.01μF
3.3V or 2.5V
.01μF
VDD
C1
X1
Crystal
C2
XTAL_IN
XTAL_OUT
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
7
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
8
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
3.3V, 2.5V LVDS DRIVER TERMINATION
A general LVDS interface is shown in Figure 3. In a 100Ω
differential transmission line environment, LVDS drivers
require a matched load termination of 100Ω across near
FIGURE 3. TYPICAL LVDS DRIVER TERMINATION
the receiver input. For a multiple LVDS outputs buffer, if only
partial outputs are used, it is recommended to terminate the
un-used outputs.
2.5V or 3.3V
+
-
VDD
100 Ohm Differential Transmission Line
R1
100
LVDS_Driv er
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
8
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
9
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
RELIABILITY INFORMATION
TRANSISTOR COUNT
The transistor count for ICS844051I is: 2395
TABLE 6. θJAVS. AIR FLOW TABLE FOR 8 LEAD TSSOP
θθ
θθ
θJA by Velocity (Meters per Second)
0 1 2.5
Multi-Layer PCB, JEDEC Standard Test Boards 101.7°C/W 90.5°C/W 89.8°C/W
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
9
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
10
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
PACKAGE OUTLINE - G SUFFIX FOR 8 LEAD TSSOP
TABLE 7. PACKAGE DIMENSIONS
Reference Document: JEDEC Publication 95, MO-153
LOBMYS sretemilliM
muminiMmumixaM
N8
A--02.1
1A50.051.0
2A08.050.1
b91.003.0
c90.002.0
D09.201.3
ECISAB04.6
1E03.405.4
eCISAB56.0
L54
.057.0
α°0°8
aaa--01.0
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
10
844051CGI www.icst.com/products/hiperclocks.html REV. A NOVEMBER 23, 2005
11
Integrated
Circuit
Systems, Inc.
ICS844051I
FEMTOCLOCKS™ C RYSTAL-TO- LVDS
CLOCK GENERATOR
PRELIMINARY
TABLE 8. ORDERING INFORMATION
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use
or for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use
in normal commercial and industrial applications. Any other applications such as those requiring high reliability or other extraordinary environmental requirements are not
recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product
for use in life support devices or critical medical instruments.
The aforementioned trademarks, HiPerClockS and FemtoClocks are trademarks of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries.
rebmuNredrO/traPgnikraMegakcaPgnigakcaPgnippihSerutarepmeT
IGC150448SCIIC154POSSTdaeL8ebutC°58otC°04-
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ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
IDT™ / ICS™ FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR ICS844051I
11
© 2006 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT and the IDT logo are trademarks of Integrated Device
Technology, Inc. Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be trademarks or registered
trademarks used to identify products or services of their respective owners.
Printed in USA
XX-XXXX-XXXXX
Corporate Headquarters
Integrated Device Technology, Inc.
6024 Silver Creek Valley Road
San Jose, CA 95138
United States
800 345 7015
+408 284 8200 (outside U.S.)
Asia Pacific and Japan
Integrated Device Technology
Singapore (1997) Pte. Ltd.
Reg. No. 199707558G
435 Orchard Road
#20-03 Wisma Atria
Singapore 238877
+65 6 887 5505
Europe
IDT Europe, Limited
Prime House
Barnett Wood Lane
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United Kingdom KT22 7DE
+44 1372 363 339
For Sales
800-345-7015
408-284-8200
Fax: 408-284-2775
For Tech Support
clockhelp@idt.com
408-284-8200
Innovate with IDT and accelerate your future networks. Contact:
www.IDT.com
ICS252
FIELD PROGRAMMABLE DUAL OUTPUT SS VERSACLOCK SYNTHESIZER TSD
ICS650-40A
ETHERNET SWITCH CLOCK SOURCE TSD
ICS1493-17
Clock Synthesizer for Portable Systems TSD
ICS3726-02
HIGH PERFORMANCE VCXO TSD
ICS844051I
FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR TSD
