ICS84330C Datasheet, PDF (9/19 Pages) Integrated Circuit Systems – 700MHZ, LOW JITTER, CRYSTAL-TO-3.3V DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
ICS84330C
700MHZ, LOW JITTER, CRYSTAL-TO-3.3V
DIFFERENTIAL LVPECL FREQUENCY SYNTHESIZER
LVCMOS TO XTAL INTERFACE
The XTAL1 input can accept single ended LVCMOS signal
through an AC couple capacitor. A general interface diagram
is shown in Figure 4. The XTAL2 input can be left floating. The
edge rate can be as slow as 10ns. If the incoming signal has
sharp edge rate and the signal path is a long trace, proper
termination for the driver and controlled characteristic imped-
ance trace may be required. The input can function with half
swing amplitude. Reducing amplitude from full swing of 3.3V
to half swing of about 1.65V can prevent signal interfere with
power rail and may reduce noise. Please refer to the LVCMOS
driver data sheet and application note for amplitude reduction
and termination approach.
VDD
Q1
LVCMOS_Driver
C1
0.1uF
XTAL1
XTAL2 _{Crystal Input Interface}
Figure 4. GENERAL DIAGRAM FOR LVCMOS DRIVER TO XTAL INPUT INTERFACE
50
40
30
20
10
0
200
Spec Limit
N=1
300
400
500
600
700
Output Frequency (MHz)
FIGURE 5. CYCLE-TO-CYCLE JITTER VS. fOUT (using a 16MHz XTAL)
84330CV
www.icst.com/products/hiperclocks.html
9
REV. B DECEMBER 7, 2004