Offset Lock Loop (part of A15)
The 285 MHz to 297.2 MHz sampling oscillator is used to sample the YTO. The frequency
can be changed by changing the programmable dividers of the offset lock loop.
,-
YTO PLL
-,
,p
FRACTIONAL N
PLL-------\
1ST
LO OUTPUT
3.0
-
6.81
GHz
/
OFFSET LOCK LOOP-,
300 MHz
t,-REFERENCE
PLL--,
600
MHz
A
L
-@
10 MHz ocxo
spi13e
Figure 7-5. Phase Lock Loops
Fractional N PLL (part of A14)
The fractional N PLL produces an output of 60 MHz to 96 MHz. This PLL output serves as
the reference frequency for the YTO PLL. A one-to-one relationship in frequency tracking
exists between the fractional N PLL and the YTO. A change of 1 MHz in the fractional
N PLL will produce a 1 MHz change in the YTO frequency.
General Troubleshooting 7-47