Integrated
Circuit
Systems, Inc.
ICS8501
LOW SKEW, 1-TO-16 DIFFERENTIAL CURRENT MODE
FANOUT BUFFER
8501BY www.icst.com/products/hiperclocks.html REV. B OCTOBER 3, 2003
7
FIGURE 2C. HIPERCLOCKS CLK/NCLK INPUT DRIVEN BY
3.3V LVPECL DRIVER
FIGURE 2B. HIPERCLOCKS CLK/NCLK INPUT DRIVEN BY
3.3V LVPECL DRIVER
FIGURE 2D. HIPERCLOCKS CLK/NCLK INPUT DRIVEN BY
3.3V LVDS DRIVER
3.3V
R1
50
R3
50
Zo = 50 Ohm
LVPECL
Zo = 50 Ohm
HiPerClockS
CLK
nCLK
3.3V
Input
R2
50
Zo = 50 Ohm
Input
HiPerClockS
CLK
nCLK
3.3V
R3
125
R2
84
Zo = 50 Ohm
3.3V
R4
125
LVPECL
R1
84
3.3V
DIFFERENTIAL CLOCK INPUT INTERFACE
The CLK /nCLK accepts LVDS, LVPECL, LVHSTL, SSTL, HCSL
and other differential signals. Both V
SWING
and V
OH
must meet the
V
PP
and V
CMR
input requirements. Figures 2A to 2D show inter-
face examples for the HiPerClockS CLK/nCLK input driven by
the most common driver types. The input interfaces suggested
FIGURE 2A. HIPERCLOCKS CLK/NCLK INPUT DRIVEN BY
ICS HIPERCLOCKS LVHSTL DRIVER
here are examples only. Please consult with the vendor of the
driver component to confirm the driver termination requirements.
For example in
Figure 2A,
the input termination applies for ICS
HiPerClockS LVHSTL drivers. If you are using an LVHSTL driver
from another vendor, use their termination recommendation.
1.8V
R2
50
Input
LVHSTL Driver
ICS
HiPerClockS
R1
50
LVHSTL
3.3V
Zo = 50 Ohm
Zo = 50 Ohm
HiPerClockS
CLK
nCLK
Zo = 50 Ohm
R1
100
3.3V
LVDS_Driv er
Zo = 50 Ohm
Receiver
CLK
nCLK
3.3V
