ICS843002I Datasheet, PDF (1/16 Pages) Integrated Circuit Systems – FEMTOCLOCKS-TM CRYSTAL-TO-3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
ICS843002I
FEMTOCLOCKS™ CRYSTAL-TO-3.3V, 2.5V
LVPECL FREQUENCY SYNTHESIZER
GENERAL DESCRIPTION
The ICS843002I is a 2 output LVPECL synthesizer
ICS
optimized to generate Fibre Channel reference
HiPerClockS™ _{clock frequencies and is a member of the}
HiPerClocks^TM family of high performance clock
solutions from ICS. Using a 26.5625MHz, 18pF
parallel resonant crystal, the following frequencies can be
generated based on the 2 frequency select pins (F_SEL[1:0]):
212.5MHz, 187.5MHz, 159.375MHz, 106.25MHz, and
53.125MHz. The ICS843002I uses ICS’ FemtoClock^TM low
phase noise VCO technology and can achieve 1ps or lower
typical rms phase jitter, easily meeting Fibre Channel jitter
requirements. The ICS843002I is packaged in a small 20-pin
TSSOP package.
FEATURES
• Two 3.3V or 2.5V LVPECL outputs
• Selectable crystal oscillator interface
or LVCMOS/LVTTL single-ended input
• Supports the following output frequencies: 212.5MHz,
187.5MHz, 159.375MHz, 106.25MHz and 53.125MHz
• VCO range: 560MHz - 680MHz
• RMS phase jitter @212.5MHz (2.55MHz - 20MHz):
0.50ps (typical)
• Full 3.3V or 2.5V supply modes
• -40°C to 85°C ambient operating temperature
• Available in both standard and lead-free RoHS compliant
packages
FREQUENCY SELECT FUNCTION TABLE
Input
Frequency
26.5625
F_SEL1
0
Inputs
F_SEL0
M Divider
Value
0
24
N Divider
Value
3
M/N
Divider Value
8
Output
Frequency
(MHz)
212.5
26.5625
0
1
24
4
6
159.375
26.5625
1
0
24
6
4
106.25
26.5625
1
1
24
12
2
53.125
23.4375
0
0
24
3
8
187.5
BLOCK DIAGRAM
F_SEL[1:0] ^Pulldown
nPLL_SEL ^Pulldown
REF_CLK ^Pulldown
1
26.5625MHz
XTAL_IN
OSC
0
XTAL_OUT
nXTAL_SEL ^Pulldown
2
Phase
Detector
1
VCO
637.5MHz
0
(w/26.5625MHz
Reference)
F_SEL[1:0]
0 0 ÷3
0 1 ÷4
1 0 ÷6
1 1 ÷12
PIN ASSIGNMENT
nc 1
2 0 VCCO
VCCO 2
19 _Q1
Q0 3 18 nQ1
nQ0 4
17 _VEE
MR 5
16 _VCC
nPLL_SEL 6 15 nXTAL_SEL
nc 7 14 REF_CLK
VCCA 8
13 _{XTAL_IN}
F_SEL0 9 12 XTAL_OUT
VCC 10 11 F_SEL1
ICS843002I
20-Lead TSSOP
6.5mm x 4.4mm x 0.92mm
package body
G Package
Top View
Q0
nQ0
Q1
nQ1
M = 24 (fixed)
MR ^Pulldown
843002AGI
www.icst.com/products/hiperclocks.html
1
REV. A JANUARY 4, 2006