PCI EXPRESS™ JITTER ATTENUATOR
ICS874003-02
GENERAL DESCRIPTION
FEATURES
• Three Differential LVDS output pairs
The ICS874003-02 is a high performance Dif-
ICS
ferential-to-LVDS Jitter Attenuator designed for
use in PCI Express systems. In some PCI Express
systems, such as those found in desktop PCs, the
PCI Express clocks are generated from a low
HiPerClockS™
• One Differential clock input
• CLK and nCLK supports the following input types:
LVPECL, LVDS, LVHSTL, SSTL, HCSL
bandwidth, high phase noise PLL frequency synthesizer. In
these systems, a jitter attenuator may be required to attenuate
high frequency random and deterministic jitter components
from the PLL synthesizer and from the system board. The
ICS874003-02 has a bandwidth of 400kHz. The 400kHz
provides an intermediate bandwidth that can easily track
triangular spread profiles, while providing good jitter
attenuation.
• Output frequency range: 98MHz - 320MHz
• Input frequency range: 98MHz - 128MHz
• VCO range: 490MHz - 640MHz
• Cycle-to-cycle jitter: 35ps (maximum)
• Supports PCI-Express Spread-Spectrum Clocking
• The 400kHz bandwidth mode allows the system designer to
make jitter attenuation/tracking skew design trade-offs
The ICS874003-02 uses IDT’s 3rd Generation FemtoClockTM
PLL technology to achive the lowest possible phase noise.
The device is packaged in a 20 Lead TSSOP package, making
it ideal for use in space constrained applications such as PCI
Express add-in cards.
• 3.3V operating supply
• 0°C to 70°C ambient operating temperature
• Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
F_SEL[2:0] FUNCTION TABLE
Inputs
F_SEL2 F_SEL1 F_SEL0 QA0/nQA0, QA0/nQA0 QB0/nQB0
Outputs
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
÷2
÷5
÷4
÷2
÷2
÷5
÷4
÷4
÷2
÷2
÷2
÷4
÷5
÷4
÷5
÷4
BLOCK DIAGRAM
Pullup
OEA
3
Pulldown
PIN ASSIGNMENT
F_SEL2:0
QA0
nQA1
VDDO
QB0
QA1
VDDO
QA0
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
÷5
÷4
nQA0
QA1
÷2 (default)
nQB0
nQA0
F_SEL2
OEB
GND
nCLK
CLK
MR
F_SEL0
nc
VDDA
F_SEL1
Pulldown
CLK
Phase
Detector
VCO
nQA1
Pullup
nCLK
490 - 640MHz
3
OEA
VDD
QB0
÷5
÷4
ICS874003-02
20-Lead TSSOP
6.5mm x 4.4mm x 0.92mm
package body
÷2 (default)
nQB0
M = ÷5 (fixed)
Pulldown
MR
G Package
Top View
Pullup
OEB
IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR
1
ICS874003AG-02 REVA AUGUST 29, 2006