843021AGI-01 www.icst.com/products/hiperclocks.html REV. A NOVEMBER 30, 2004
1
Integrated
Circuit
Systems, Inc.
ICS843021I-01
FEMTOCLOCKS™ C RYSTAL-TO-3.3V, 2.5V
125MHZ LVPECL CLOCK GENERATOR
PRELIMINARY
GENERAL DESCRIPTION
The ICS843021I-01 is a Gigabit Ethernet Clock
Generator and a member of the HiPerClocks
TM
family of high performance devices from ICS. The
ICS843021I-01 uses a 25MHz crystal to
synthesize 125MHz. The ICS843021I-01 has
excellent phase jitter performance, over the 1.875MHz – 20MHz
integration range. The ICS843021I-01 is packaged in a small
8-pin TSSOP, making it ideal for use in systems with limited
board space.
FEATURES
• 1 differential 3.3V LVPECL output
• Crystal oscillator interface designed for 25MHz,
18pF parallel resonant crystal
• Output frequency: 125MHz, using a 25MHz crystal
• VCO range: 490MHz - 640MHz
• RMS phase jitter @ 125MHz, using a 25MHz crystal
(1.875MHz - 20MHz): 0.41ps (typical) (for 3.3V)
• Full 3.3V or 2.5V operating supply
• -40°C to 85°C ambient operating temperature
HiPerClockS™
ICS
ICS843021I-01
8-Lead TSSOP
4.40mm x 3.0mm x 0.925mm package body
G Package
Top View
VCC
XTAL_OUT
XTAL_IN
VEE
1
2
3
4
Q0
nQ0
VCC
OE
8
7
6
5
BLOCK DIAGRAM PIN ASSIGNMENT
OSC
Phase
Detector
VCO
÷4
(fixed)
÷20
(fixed)
XTAL_IN
XTAL_OUT
Q0
nQ0
25MHz
OE
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.