889831AK www.icst.com/products/hiperclocks.html REV. A JUNE 16, 2005
10
Integrated
Circuit
Systems, Inc.
ICS889831
LOW SKEW, 1-TO-4
DIFFERENTIAL LVPECL-TO-LVPECL/ECL FANOUT BUFFER
2.5V LVPECL INPUT WITH BUILT-IN 50
ΩΩ
ΩΩ
Ω TERMINATION INTERFACES
The IN /nIN with built-in 50Ω terminations accepts LVDS,
LVPECL, LVHSTL, CML, SSTL and other differential signals.
Both V
OUT
and V
OH
must meet the V
PP
and V
CMR
input
requirements.
Figures 4A to 4D
show interface examples for the
HiPerClockS IN/nIN input with built-in 50Ω terminations driven
by the most common driver types. The input interfaces sug-
gested here are examples only. If the driver is from another ven-
dor, use their termination recommendation. Please consult with
the vendor of the driver component to confirm the driver termi-
nation requirements.
FIGURE 4A. HIPERCLOCKS IN/nIN INPUT WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω DRIVEN BY AN LVDS DRIVER
FIGURE 4B. HIPERCLOCKS IN/nIN INPUT WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω DRIVEN BY AN LVPECL DRIVER
IN
nIN
VT
2.5V
LVDS
3.3V or 2.5V
Zo = 50 Ohm
Zo = 50 Ohm
Receiver
With
Built-In
50 Ohm
Zo = 50 Ohm
Receiver
With
Built-In
50 Ohm
Zo = 50 Ohm
IN
nIN
VT
2.5V2.5V
R1
18
2.5V LVPECL
FIGURE 4E. HIPERCLOCKS IN/nIN INPUT WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω DRIVEN BY AN SSTL DRIVER
FIGURE 4C. HIPERCLOCKS IN/nIN INPUT WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω DRIVEN BY AN OPEN COLLECTOR
CML DRIVER
FIGURE 4D. HIPERCLOCKS IN/nIN INPUT WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω DRIVEN BY A CML DRIVER
WITH
BUILT-IN 50
ΩΩ
ΩΩ
Ω PULLUP
Zo = 50 Ohm
2.5V
Zo = 50 Ohm
IN
nIN
VT
Receiver
With
Built-In
50 Ohm
2.5V
CML - Open Collector
IN
nIN
VT
Receiver
With
Built-In
50 Ohm
2.5V
Zo = 50 Ohm
Zo = 50 Ohm
CML - Built-in 50 Ohm Pull-up
2.5V
2.5V
2.5V
SSTL
R1 25
R2 25
IN
VT
nIN
Receiver With Built-In 50Ω
Zo = 50 Ohm
Zo = 50 Ohm
