PRELIMINARY
PCI EXPRESS™ CLOCK GENERATOR
ICS841S01
GENERAL DESCRIPTION
FEATURES
The ICS841S01 is a PLL-based clock generator
• One 0.7V current mode differential HCSL output pair
• Crystal oscillator interface, 25MHz
ICS
HiPerClockS™
specifically designed for PCI_Express™Clock
Generation applications. This device generates a
100MHz HCSL clock. The device offers a HCSL
(Host Clock Signal Level) clock output from a clock
• Output frequency: 100MHz
• RMS period jitter: 3ps (maximum)
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 may be applied
to the XTAL_IN pin with the XTAL_OUT pin left floating.
• Cycle-to-cyle jitter: 35ps (maximum)
• I2C support with readback capabilities up to 400kHz
• Spread Spectrum for electromagnetic interference (EMI)
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 select either a down spread
value of -0.35% or -0.5%.
reduction
• 3.3V operating supply mode
• 0°C to 70°C ambient operating temperature
• Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
The ICS841S01 is available in both standard and lead-free
16-Lead TSSOP packages.
BLOCK DIAGRAM
PIN ASSIGNMENT
25MHz
VSS_SRC
VDD_SRC
SRCT0
SRCC0
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
VDD_SRC
SDATA
XTAL_IN
SRCT0
SRCC0
Divider
Network
OSC
PLL
SCLK
XTAL_OUT
XTAL_IN
VDD_REF
VSS_REF
VDDA
XTAL_OUT
VDD_SRC
VSS_SRC
IREF
Pullup
SDATA
SCLK
I2C
Logic
VSSA
Pullup
ICS841S01
16-Lead TSSOP
4.4mm x 5.0mm x 0.92mm
package body
IREF
G Package
Top View
The Preliminary Information presented herein represents a product in pre-production.The noted characteristics are based on initial product characterization
and/or qualification.Integrated DeviceTechnology, Incorporated (IDT) reserves the right to change any circuitry or specifications without notice.
IDT™ / ICS™ PCI EXPRESS CLOCK GENERATOR
1
ICS841S01BG REV. B MAY 23, 2007