ICS840-125 Datasheet, PDF (6/9 Pages) Integrated Circuit Systems – 125MHZ, LVCMOS/LVTTL OSCILLATOR REPLACEMENT

Integrated
Circuit
Systems, Inc.
ICS840-125
125MHZ, LVCMOS/LVTTL
OSCILLATOR REPLACEMENT
APPLICATION INFORMATION
CRYSTAL INPUT INTERFACE
The ICS840-125 has been characterized with 18pF parallel
resonant crystals. The capacitor values, C1 and C2, shown in
Figure 1 below were determined using a 25MHz, 18pF paral-
lel resonant crystal and were chosen to minimize the ppm
error. The optimum C1 and C2 values can be slightly adjusted
for different board layouts.
X1
18pF Parallel Cry stal
XTAL_OUT
C1
12p
XTAL_IN
C2
12p
Figure 1. CRYSTAL INPUt INTERFACE
840AG-125
www.icst.com/products/hiperclocks.html
6
REV. A FEBRUARY 3, 2006