ICS9DB306
PCI EXPRESS,
JITTER ATTENUATOR
Integrated
Circuit
Systems, Inc.
GENERAL DESCRIPTION
Features
The ICS9DB306 is a high performance 1-to-6
• Six differential LVPECL output pairs
ICS
Differential-to LVPECL 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
• One differential clock input
HiPerClockS™
• CLK and nCLK supports the following input types:
LVPECL, LVDS, LVHSTL, SSTL, HCSL
synthesizer. In these systems, a zero delay buffer may be
required to attenuate high frequency random and deterministic
jitter components from the PLL synthesizer and from the system
board. The ICS9DB306 has 2 PLL bandwidth modes. In low
bandwidth mode, the PLL loop BW is about 500kHz and this
setting will attenuate much of the jitter from the reference clock
input while being high enough to pass a triangular input spread
spectrum profile. There is also a high bandwidth mode which
• Maximum output frequency: 140MHz
• Output skew: 135ps (maximum)
• Cycle-to-Cycle jitter: 25ps (maximum)
• RMS phase jitter @ 100MHz, (1.5MHz - 22MHz):
3ps (typical)
sets the PLL bandwidth at 1MHz which will pass more spread • 3.3V operating supply
spectrum modulation.
• 0°C to 70°C ambient operating temperature
For serdes which have x30 reference multipliers instead of x25
multipliers, 5 of the 6 PCI Express™ outputs (PCIEX1:5) can be
set for 125MHz instead of 100MHz by configuring the appropri-
ate frequency select pins (FS0:1). Output PCIEX0 will always
run at the reference clock frequency (usually 100MHz) in desk-
top PC PCI Express™ Applications.
• Available in both standard and lead-free RoHS compliant
packages
• Industrial temperature information available upon request
BLOCK DIAGRAM
PIN ASSIGNMENT
1 Disabled
0 Enabled
nOE0
1
2
3
4
28
27
26
25
VEE
PCIEXT1
PCIEXC1
PCIEXT2
PCIEXC2
VCC
VCC
PCIEXC0
PCIEXT0
FS0
nCLK
CLK
PLL_BW
VCCA
VEE
0
1
PCIEXT0
nPCIEXC0
÷5
24
23
22
21
20
5
6
7
8
Buffer
nOE0
nOE1
VCC
9
CLK
Loop
Filter
PCIEXT1
nPCIEXC1
0
1
Phase
Detector
BYPASS
FS1
0 ÷4
PCIEXC3
10
11
12
13
19
18
17
16
15
VCO
nCLK
PCIEXT3
PCIEXC4
PCIEXT4
VEE
1 ÷5
PCIEXT2
nPCIEXC2
PCIEXT5
PCIEXC5
VCC
14
FS0
÷5
ICS9DB306
28-LeadTSSOP, 173-MIL
4.4mm x 9.7mm x 0.92mm
body package
Internal Feedback
PCIEXT3
nPCIEXC3
0
1
0 ÷5
1 ÷4
L Package
TopView
PCIEXT4
nPCIEXC4
ICS9DB306
28-Lead, 209-MIL SSOP
5.3mm x 10.2mm x 1.75mm
body package
PCIEXT5
nPCIEXC5
FS1
F Package
BYPASS
nOE1
TopView
1 Disabled
0 Enabled
9DB306BL
www.icst.com/products/hiperclocks.html
REV.B JUNE 16, 2006
1