ICS844021I-01 Datasheet, PDF (1/13 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO- LVDS CLOCK GENERATOR

PRELIMINARY
FEMTOCLOCKS™ CRYSTAL-TO-LVDS
CLOCK GENERATOR
GENERAL DESCRIPTION
The ICS844021I-01 is an Ethernet Clock Generator
ICS
and a member of the HiPerClocks^TM family of high
HiPerClockS™ _{performance devices from IDT. The ICS844021I-}
01 uses an 18pF parallel resonant crystal over the
range of 24.5MHz – 34MHz. For Ethernet appli-
cations, a 25MHz crystal is used. The ICS844021I-01 has
excellent <1ps phase jitter performance, over the 1.875MHz –
20MHz integration range. The ICS844021I-01 is packaged in a
small 8-pin TSSOP, making it ideal for use in systems with
limited board space.
ICS844021I-01
FEATURES
• One Differential LVDS output
• Crystal oscillator interface, 18pF parallel resonant crystal
(24.5MHz – 34MHz)
• Output frequency range: 122.5MHz – 170MHz
• VCO range: 490MHz – 680MHz
• RMS phase jitter @ 125MHz, using a 25MHz crystal
(1.875MHz – 20MHz): 0.32ps (typical) @ 3.3V
• 3.3V or 2.5V operating supply
• -40°C to 85°C ambient operating temperature
• Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
COMMON CONFIGURATION TABLE - Gb ETHERNET
Inputs
Crystal Frequency (MHz) M
25
20
26.666
20
33.33
20
N
Multiplication
Value M/N
4
5
4
5
4
5
Output Frequency
(MHz)
125
133.33
166.66
BLOCK DIAGRAM
OE ^Pullup
XTAL_IN
OSC
Phase
Detector
VCO
490MHz - 680MHz
N = ÷4 (fixed)
Q
nQ
XTAL_OUT
M = ÷20 (fixed)
PIN ASSIGNMENT
VDDA 1
GND 2
XTAL_OUT 3
XTAL_IN 4
8 VDD
7Q
6 nQ
5 OE
ICS844021I-01
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 pre-production. The noted characteristics are based on initial product characterization
and/or qualification. Integrated Device Technology, Incorporated (IDT) reserves the right to change any circuitry or specifications without notice.
IDT^™ / ICS^™ LVDS CLOCK GENERATOR
1
ICS844021BGI-01 REV. C SEPTEMBER 27, 2007