PCI EXPRESS™ JITTER ATTENUATOR ICS874003I-02
IDT
™
/ ICS
™
PCI EXPRESS™ JITTER ATTENUATOR 1 ICS874003AGI-02 REV A MAY 1, 2013
÷5
÷4
÷2
(default)
÷5
÷4
÷2
(default)
VCO
490 - 640MHz
Phase
Detector
M = ÷5
(fixed)
3
QA0
nQA0
QA1
nQA1
QB0
nQB0
Pullup
Pulldown
Pulldown
Pullup
Pulldown
Pullup
OEA
F_SEL2:0
CLK
nCLK
MR
OEB
3
GENERAL DESCRIPTION
The ICS874003I-02 is a high performance Dif-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
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 ICS874003I-
02 has a bandwidth of 400kHz. The 400kHz provides an
intermediate bandwidth that can easily track triangular spread
profiles, while providing good jitter attenuation.
The ICS874003I-02 uses IDT’s 3
rd
Generation FemtoClock
TM
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.
FEATURES
• Three Differential LVDS output pairs
• One Differential clock input
• CLK and nCLK supports the following input types:
LVPECL, LVDS, LVHSTL, SSTL, HCSL
• 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
• 3.3V operating supply
• -40°C to 85°C ambient operating temperature
• Lead-free (RoHS 6) packaging
BLOCK DIAGRAM
PIN ASSIGNMENT
ICS874003I-02
20-Lead TSSOP
6.5mm x 4.4mm x 0.92mm
package body
G Package
Top View
F_SEL[2:0] FUNCTION T ABLE
stupnIstuptuO
2LES_F1LES_F0LES_F1AQn,1AQ:0AQn,0AQ0BQn,0BQ
000 2÷2÷
10 0 5÷2÷
010 4÷2÷
110 2÷4÷
00 1 2÷5÷
10 1 5÷4÷
011 4÷5÷
111 4÷4÷
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
F_SEL1
V
DDA
nc
F_SEL0
MR
nQA0
QA0
V
DDO
QA1
V
DD
nQA1
V
DDO
QB0
nQB0
F_SEL2
OEB
GND
nCLK
CLK
OEA
