Crystal-to-LVPECL 133MHz
Clock Synthesizer
ICS843S104I-133
DATA SHEET
General Description
The ICS843S104I-133 is a PLL-based clock
ICS synthesizer specifically designed for low phase noise
HiPerClockS™ applications. This device generates a 133.33MHz
differential LVPECL clock from an input reference of
25MHz. The input reference may be derived from an
external source or by the addition of a 25MHz crystal to the on-chip
crystal oscillator. An external reference is applied to the PCLK,
nPCLK pins.The device offers spread spectrum clock output for
reduced EMI applications. An I2C bus interface is used to enable or
disable spread spectrum operation as well as to select either a down
spread value of -0.35% or -0.5%.The ICS843S104I-133 is available
in a lead-free 32-Lead VFQFN package.
Features
• Four LVPECL output pairs
• Crystal oscillator interface: 25MHz
• Differential PCLK/nPCLK input pair
• PCLK/nPCLK supports the following input types: LVPECL, CML,
SSTL
• Output frequency: 133.33MHz
• PCI Express (2.5 Gb/s) and Gen 2 (5 Gb/S) jitter compliant
• RMS phase jitter @ 133.33MHz (12kHz – 20MHz):
1.2ps (typical)
• I2C support with readback capabilities up to 400kHz
• Spread Spectrum for electromagnetic interference (EMI) reduction
• 3.3V operating supply mode
• -40°C to 85°C ambient operating temperature
• Available lead-free (RoHS 6) package
Block Diagram
REF_SEL Pulldown
PCLK Pulldown
nPCLK Pullup/Pulldown
25MHz
XTAL_IN
OSC
XTAL_OUT
SDATA Pullup
SCLK Pullup
1
PLL
0
I2C
Logic
4
Q[1:4]
4
nQ[1:4]
Pin Assignment
32 31 30 29 28 27 26 25
VCC 1
24 VEE
REF_SEL 2
23 nQ3
VEE 3
22 Q3
PCLK 4
21 VCC
nPCLK 5
20 VEE
VEE 6
19 nQ4
VCCA 7
18 Q4
VEE 8
17 VCC
9 10 11 12 13 14 15 16
ICS843S104I-133
32-Lead VFQFN
5.0mm x 5.0mm x 0.925mm
package body
K Package
Top View
ICS843S104BKI-133 REVISION A JUNE 9, 2009
1
©2009 Integrated Device Technology, Inc.
