ICS840002I
FEMTOCLOCKS™ CRYSTAL-TO-
LVCMOS/LVTTL FREQUENCY SYNTHESIZER
Integrated
Circuit
Systems, Inc.
GENERAL DESCRIPTION
FEATURES
• Two LVCMOS outputs @ 3.3V, 17Ω typical output impedance
The ICS840002I is a 2 output LVCMOS/LVTTL
ICS
Synthesizer optimized to generate Fibre Channel
reference clock frequencies and is a member of
the HiPerClocksTM family of high performance
clock solutions from ICS. Using a 26.5625MHz
• Selectable crystal oscillator interface
or LVCMOS single-ended input
HiPerClockS™
• Output frequency range: 46.66MHz - 233.33MHz
• VCO range: 560MHz - 700MHz
18pF parallel resonant crystal, the following frequencies can be
generated based on the 2 frequency select pins (F_SEL1:0):
212.5MHz, 159.375MHz, 156.25MHz, 106.25MHz, and
53.125MHz.The ICS840002I uses ICS’3rd generation low phase
noise VCO technology and can achieve 1ps or lower typical
rms phase jitter, easily meeting Fibre Channel jitter requirements.
The ICS840002I is packaged in a 16-pin TSSOP package.
• Supports the following output frequencies: 212.5MHz,
159.375MHz, 156.25MHz, 106.25MHz and 53.125MHz
• RMS phase jitter @ 212.5MHz (637KHz - 10MHz):
0.83ps (typical)
Typical phase noise at 212.5MHz:
Offset
Noise Power
100Hz ............... -91.3 dBc/Hz
1KHz ..............-114.3 dBc/Hz
10KHz ..............-120.7 dBc/Hz
100KHz ..............-120.2 dBc/Hz
• Power supply modes:
Core/Output
3.3V/3.3V
3.3V/2.5V
2.5V/2.5V
• -40°C to 85°C ambient operating temperature
• Lead-Free package RoHS compliant
FREQUENCY SELECT FUNCTION TABLE
Inputs
F_SEL1 F_SEL0 M Divider Value N Divider Value M/N Ratio Value
Input Frequency
(MHz)
Output Frequency
(MHz)
26.5625
26.5625
26.5625
26.5625
26.04166
0
0
1
1
0
0
1
0
1
1
24
24
24
24
24
3
4
8
6
4
2
6
212.5
159.375
106.25
53.125
156.25
6
12
4
BLOCK DIAGRAM
PIN ASSIGNMENT
Pullup
OE
1
2
3
4
5
6
7
8
F_SEL0
nXTAL_SEL
TEST_CLK
OE
MR
nPLL_SEL
VDDA
16
15
14
13
12
11
10
9
F_SEL1
GND
GND
Q0
Q1
VDDO
XTAL_IN
XTAL_OUT
2
Pullup:Pullup
F_SEL1:0
Pulldown
nPLL_SEL
Pulldown
nXTAL_SEL
26.5625MHz
XTAL_IN
VDD
F_SEL1:0
N
0
Q0
Q1
OSC
1
0
ICS840002I
16-LeadTSSOP
4.4mm x 5.0mm x 0.92mm
package body
0 0 ÷3
XTAL_OUT
Pulldown
0 1 ÷4
Phase
Detector
1
TEST_CLK
VCO
1 0 ÷6
1 1 ÷12 (default)
G Package
Top View
M = ÷24 (fixed)
Pulldown
MR
840002AGI
www.icst.com/products/hiperclocks.html
REV. A MARCH 10, 2005
1