
Integrated
Circuit
Systems, Inc.
840004AGI
www.icst.com/products/hiperclocks.html
REV. A JUNE 28, 2005
1
ICS840004I
F
EMTO
C
LOCKS
C
RYSTAL
-
TO
-
LVCMOS/LVTTL F
REQUENCY
S
YNTHESIZER
PRELIMINARY
G
ENERAL
D
ESCRIPTION
The ICS840004I is a 4 output LVCMOS/LVTTL
Synthesizer optimized to generate Fibre Channel
reference 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_SEL1:0):
212.5MHz, 159.375MHz, 156.25MHz, 106.25MHz, and
53.125MHz. The ICS840004I uses ICS’ 3
rd
generation low phase
noise VCO technology and can achieve 1ps or lower typical
random rms phase jitter, easily meeting Fibre Channel jitter
requirements. The ICS840004I is packaged in a small 20-pin
TSSOP package.
HiPerClockS
ICS
B
LOCK
D
IAGRAM
F
EATURES
Four LVCMOS/LVTTL outputs, 15
Ω
typical output impedance
Selectable crystal oscillator interface
or LVCMOS single-ended input
Supports the following input frequencies: 212.5MHz,
159.375MHz, 156.25MHz, 106.25MHz and 53.125MHz
RMS phase jitter @ 212.5MHz(2.55MHz - 20MHz):
0.49ps (typical)
Output supply modes:
Core/Output
3.3V/3.3V
3.3V/2.5V
2.5V/2.5V
-40°C to 85°C ambient operating temperature
Q0
Q1
Q2
Q3
OE
F_SEL1:0
nPLL_SEL
nXTAL_SEL
XTAL_IN
XTAL_OUT
TEST_CLK
MR
OSC
Phase
Detector
VCO
M = ÷24 (fixed)
F_SEL1:0
0 0 ÷3
0 1 ÷4
1 0 ÷6
1 1 ÷12
(default)
0
1
1
0
2
N
26.5625MHz
Pullup
Pulldown
Pulldown
Pulldown
Pullup:Pullup
Pulldown
F
REQUENCY
S
ELECT
F
UNCTION
T
ABLE
P
IN
A
SSIGNMENT
ICS840004I
20-Lead TSSOP
6.5mm x 4.4mm x 0.92mm
package body
G Package
Top View
F_SEL0
nc
nXTAL_SEL
TEST_CLK
OE
MR
nPLL_SEL
V
DDA
nc
V
DD
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
F_SEL1
GND
Q0
Q1
V
DDO
Q2
Q3
GND
XTAL_IN
XTAL_OUT
s
u
p
n
y
c
n
e
)
u
H
q
M
e
(
r
F
e
t
u
n
a
p
t
R
u
O
g
y
c
n
e
u
q
)
2
6
2
6
2
6
2
6
1
4
e
H
r
F
M
(
5
2
5
2
5
2
5
2
0
2
t
u
p
n
1
L
E
S
_
F
0
L
E
S
_
F
r
e
d
D
u
V
4
2
4
2
4
2
4
2
4
2
M
e
r
e
d
D
u
V
3
4
6
1
4
N
e
o
R
e
u
V
8
6
4
2
6
N
/
M
5
5
5
5
6
6
0
0
1
1
0
0
1
0
1
1
5
1
3
5
2
0
1
1
5
2
5
1
2
5
7
5
5
2
1
2
5
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.