Integrated

Circuit

Systems, Inc.

ICS8521

8521BY

www.icst.com/products/hiperclocks.html

REV. B JULY 31, 2001

8

Figure 9 shows how the differential input can be wired to accept single ended levels. The reference voltage V_REF ~ V

generated by the bias resistors R1, R2 and C1. This bias circuit should be located as close as possible to the input pin. The ratio of

R1 and R2 might need to be adjusted to position the V_REF in the center of the input voltage swing. For example, if the input clock

swing is only 2.5V and V

R2

1K

V

DD

CLK_IN

+

-

R1

1K

C1

0.1uF

V_REF