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ICS83940DI Datasheet, PDF (12/19 Pages) Integrated Circuit Systems – LOW SKEW, 1-TO-18 LVPECL-TO-LVCMOS / LVTTL FANOUT BUFFER
ICS83940DI Data Sheet
LOW SKEW, 1-TO-18 LVPECL-TO-LVCMOS/LVTTL FANOUT BUFFER
LVPECL Clock Input Interface
The PCLK /nPCLK accepts LVPECL, CML, SSTL and other
differential signals. Both differential signals must meet the VPP and
VCMR input requirements. Figures 2A to 2E show interface examples
for the PCLK/nPCLK input driven by the most common driver types.
The input interfaces suggested here are examples only. If the driver
is from another vendor, use their termination recommendation.
Please consult with the vendor of the driver component to confirm the
driver termination requirements.
3.3V
CML
o = 50Ω
o = 50Ω
3.3V
R1
R2
50Ω
50Ω
3.3V
PCLK
nPCLK
LVPECL
Input
3.3V
o = 50Ω
CML Built-In Pullup
o = 50Ω
R1
100Ω
3.3V
PCLK
nPCLK
LVPECL
Input
Figure 2A. PCLK/nPCLK Input Driven by a CML Driver
Figure 2B. PCLK/nPCLK Input Driven by a
Built-In Pullup CML Driver
3.3V
LVPECL
o = 50Ω
o = 50Ω
3.3V
R3
125Ω
R4
125Ω
3.3V
PCLK
nPCLK
LVPECL
R1
R2
84Ω
84Ω
Input
Figure 2C. PCLK/nPCLK Input Driven by a
3.3V LVPECL Driver
2.5V
SSTL
o = 60Ω
o = 60Ω
2.5V
R3
R4
120
120
3.3V
PCLK
R1
R2
120
120
nPCLK
LVPECL
Input
Figure 2D. PCLK/nPCLK Input Driven by a
3.3V LVPECL Driver with AC Couple
Figure 2E. PCLK/nPCLK Input Driven by an SSTL Driver
ICS83940DYI REVISION C MARCH 20, 2013
12
©2013 Integrated Device Technology, Inc.