
DATA SHEET
ICS843156AK REVISION B NOVEMBER 28, 2012
1
2012 Integrated Device Technology, Inc.
Crystal-to-LVPECL Clock Synthesizer
ICS843156
General Description
The ICS843156 is a high frequency clock generator. The ICS843156
uses an external 25MHz crystal to synthesize 156.25MHz clock. The
ICS843156 has excellent cycle-to-cycle and RMS period jitter perfor-
mance.
The ICS843156 operates at full 3.3V and 2.5V, or mixed 3.3V/2.5V
operating supplies and is available in a fully RoHS compliant 32-lead
VFQFN package.
Features
Ten differential LVPECL outputs of 156.25MHz
Crystal oscillator interface designed for 18pF, 25MHz parallel
resonant crystal
Cycle-to-cycle jitter: 40ps (maximum)
RMS phase jitter at 156.25MHz (1.875MHz - 20MHz):
0.39ps (typical)
Output Duty Cycle: 45% – 55%
Full 3.3V and 2.5V, or mixed 3.3V/2.5V supply modes
0°C to 70°C ambient operating temperature
Available in lead-free (RoHS 6) package
Output Frequency Table
Crystal Frequency (MHz)
Feedback Divider
VCO Frequency (MHz)
Output Divider
Output Frequency (MHz)
25
625
÷4
156.25
9
10 11 12 13 14 15 16
32 31 30
29 28
27 26 25
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
XTAL_IN
XTAL_OUT
VCC
nQC1
QC1
nQC0
QC0
VCCO
QA1
nQA1
QA2
nQA2
QA3
nQA3
QA4
nQA4
nQB1
QB1
nQB0
QB0
V
EE
nQA5
QA5
V
CCO
TE
S
T_CLK
V
EE
BYPA
SS
V
CCA
QA0
nQA0
V
CCO
V
CC
Block Diagram
OSC
Phase
Detector
VCO
625MHz
÷25
÷4
QA[0:5]
nQA[0:5]
nQC[0:1]
QC[0:1]
nQB[0:1]
QB[0:1]
25MHz
XTAL_IN
XTAL_OUT
BYPASS
TEST_CLK
÷4
6
2
Pulldown
1
0
32-Lead VFQFN
5mm x 5mm x 0.925mm package body
3.15mm x 3.15mm EPad
K Package
Top View
Pin Assignment
ICS843156