01280606

PROGRAMMABLE REFERENCE DIVIDERS (IF AND RF R COUNTERS)

If the Control Bits are 00 or 01 (00 for IF and 01 for RF) data is transferred from the 22-bit shift register into a latch which sets

the 15-bit R Counter. Serial data format is shown below.

01280607

15-BIT PROGRAMMABLE REFERENCE DIVIDER RATIO (R COUNTER)

Divide

RRRRRRRRRRRRRR

R

Ratio

15 14 13 12 11 10

98765432

1

3

00000000000001

1

4

00000000000010

0

•

••••••••••••••

•

32767

11111111111111

1

Notes:

Divide ratios less than 3 are prohibited.

Divide ratio: 3 to 32767

R1 to R15: These bits select the divide ratio of the programmable reference divider.

Data is shifted in MSB first.

PROGRAMMABLE DIVIDER (N COUNTER)

The N counter consists of the 7-bit swallow counter (A counter) and the 11-bit programmable counter (B counter). If the Control

Bits are 10 or 11 (10 for IF counter and 11 for RF counter) data is transferred from the 22-bit shift register into a 4-bit or 7-bit latch

(which sets the Swallow (A) Counter) and an 11-bit latch (which sets the 11-bit programmable (B) Counter), MSB first. Serial data

format is shown below. For the IF N counter bits 5, 6, and 7 are don’t care bits. The RF N counter does not have don’t care

bits.

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