Typical Application Example
DS101026-36
Operational Notes:
*
VCO is assumed AC coupled.
**
R
increases impedance so that VCO output power is provided to the load rather than the PLL. Typical values are 10
to
200
depending on the VCO power level. f
IN
RF impedance ranges from 40
to 100
. f
IN
IF impedances are higher.
***
50
termination is often used on test boards to allow use of external reference oscillator. For most typical products a
CMOS clock is used and no terminating resistor is required. OSC
may be AC or DC coupled. AC coupling is recom-
mended because the input circuit provides its own bias. (See Figure below)
****
Adding RC filters to the V
CC
line is recommended to reduce loop-to-loop noise coupling.
DS101026-37
Proper use of grounds and bypass capacitors is essential to achieve a high level of performance. Crosstalk between pins can be reduced by careful board
layout.
This is an electrostatic sensitive device. It should be handled only at static free work stations.
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