ICS844022I-02 Datasheet, PDF (1/10 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR

Integrated
Circuit
Systems, Inc.
PRELIMINARY
ICS844022I-02
FEMTOCLOCKS™CRYSTAL-TO- LVDS
CLOCK GENERATOR
GENERAL DESCRIPTION
The ICS844022I-02 is an Ethernet Clock
ICS
Generator and a member of the HiPerClocks^TM
HiPerClockS™ _{family of high performance devices from ICS. The}
ICS844022I-02 uses an 18pF parallel resonant
crystal over the range of 24.5MHz - 34MHz. For
Ethernet applications, a 25MHz crystal is used and either
62.5MHz or 125MHz may be selected with the FREQ_SEL
pin. The ICS844022I-02 has excellent <1ps phase jitter
performance, over the 1.875MHz - 20MHz integration range.
The ICS844022I-02 is packaged in a small 8-pin TSSOP,
making it ideal for use in systems with limited board space.
FEATURES
• (1) Differential LVDS output
• Crystal oscillator interface, 18pF parallel resonant crystal
(24.5MHz - 34MHz)
• Output frequency range: 61.25MHz - 170MHz
• VCO range: 490MHz - 680MHz
• RMS phase jitter @ 125MHz, using a 25MHz crystal
(1.875MHz - 20MHz): 0.44ps (typical)
• 3.3V or 2.5V operating supply
• -40°C to 85°C ambient operating temperature
COMMON CONFIGURATION TABLE - Gb ETHERNET
Inputs
Crystal Frequency (MHz) FREQ_SEL M
25
25
26.66
26.66
33.33
33.33
0
20
1
20
0
20
1
20
0
20
1
20
Output Frequency
N
Multiplication
Value M/N
(MHz)
4
5
125
8
2.5
62.5
4
5
133.33
8
2.5
66.66
4
5
166.66
8
2.5
83.33
BLOCK DIAGRAM
FREQ_SEL ^Pullup
XTAL_IN
XTAL_OUT
OSC
Phase
Detector
VCO
490MHz - 680MHz
M = ÷20 (fixed)
FREQ_SEL N
0
÷4
1
÷8
PIN ASSIGNMENT
VDDA 1
8 VDD
GND 2
7Q
XTAL_OUT 3
6 nQ
Q
XTAL_IN 4
5 FREQ_SEL
nQ
ICS844022I-02
8-Lead TSSOP
4.40mm x 3.0mm x 0.925mm
package body
G Package
Top View
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.
844022AGI-02
www.icst.com/products/hiperclocks.html
REV. A JUNE 28, 2005
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