PCI EXPRESS JITTER ATTENUATOR
ICS9DB206
GENERAL DESCRIPTION
Features
The ICS9DB206 is a high perfromance 1-to-6
• Six 0.7V current mode differential HCSL output pairs
• One differential clock input
ICS
Differential-to-HCSL 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
HiPerClockS™
• CLK and nCLK supports the following input types:
LVPECL, LVDS, LVHSTL, SSTL, HCSL
synthesizer. In these systems, a jitter-attenuating device may be
necessary in order to reduce high frequency random and
deterministic jitter components from the PLL synthesizer and from
the system board.The ICS9DB206 has two PLL bandwidth modes.
In low bandwidth mode, the PLL loop bandwidth is 500kHz. This
setting offers the best jitter attenuation and is still high enough to
pass a triangular input spread spectrum profile. In high bandwidth
mode, the PLL bandwidth is at 1MHz and allows the PLL to pass
more spread spectrum modulation.
• Maximum output frequency: 140MHz
• Input frequency range: 90MHz - 140MHz
• VCO range: 450MHz - 700MHz
• Output skew: 110ps (maximum)
• Cycle-to-Cycle jitter: 110ps (maximum)
• RMS phase jitter @ 100MHz, (1.5MHz - 22MHz):
2.42ps (typical)
For serdes which have x10 reference multipliers instead of x12.5
multipliers, 5 of the 6 PCI Express outputs (PCIEX1:5) can be
set for 125MHz instead of 100MHz by configuring the appropriate
frequency select pins (FS0:1). Output PCIEX0 will always run at
the reference clock frequency (usually 100MHz) in desktop PC
PCI Express Applications.
• 3.3V operating supply
• 0°C to 70°C ambient operating temperature
• Available in both standard and lead-free RoHS compliant
packages
• Industrial temperature information available upon request
BLOCK DIAGRAM
Current
Set
IREF
-
PIN ASSIGNMENT
+
1 HiZ
0 Enabled
1
2
3
4
PLL_BW
CLK
nCLK
28
27
26
25
VDDA
GND
IREF
FS1
nOE0
÷5
PCIEXT0
FS0
nPCIEXC0
PCIEXT0
PCIEXC0
VDD
PCIEXT5
PCIEXC5
VDD
24
23
22
21
20
5
6
7
8
nCLK
CLK
Loop
Filter
GND
GND
PCIEXT1
nPCIEXC1
PCIEXT2
nPCIEXC2
Phase
Detector
0 ÷4
1 ÷5
VCO
PCIEXT1
PCIEXC1
PCIEXT2
PCIEXC2
VDD
PCIEXT4
PCIEXC4
PCIEXT3
9
10
11
12
13
19
18
17
16
15
PCIEXC3
VDD
nOE1
÷5
nOE0
14
Internal Feedback
FS0
ICS9DB206
28-Lead TSSOP, 173-MIL
4.4mm x 9.7mm x 0.92mm body package
L Package
PCIEXT3
nPCIEXC3
0 ÷5
1 ÷4
PCIEXT4
nPCIEXC4
Top View
PCIEXT5
nPCIEXC5
ICS9DB206
28-Lead, 209-MIL SSOP
5.3mm x 10.2mm x 1.75mm body package
F Package
FS1
1 HiZ
0 Enabled
Top View
nOE1
IDT™ / ICS™ PCI EXPRESS JITTER ATTENUATOR
1
ICS9DB206CL REV B JULY 14, 2006