2.4 AUXILIARY R REGISTER

The Aux R register contains the Aux R_CNTR, PD_POL Aux, ID

bits that compose the F

discussed in the following sections.

Reg. Most Significant Bit

SHIFT REGISTER BIT LOCATION

Least Significant Bit

21

20

19

18

17

16

15

14

13

12

11

10

9876543210

Data Field

Address

Field

Aux

R

FoLD0 FoLD2

TRI-

STATE

IDo

Aux

IDo

Aux

PD_

POL

Aux

Aux R_CNTR[14:0]

0

0

2.4.1 Aux R_CNTR[14:0]

AUXILIARY SYNTHESIZER PROGRAMMABLE REFERENCE DIVIDER (R COUNTER)

Aux R[2:16]

The Aux reference divider (Aux R_CNTR) can be programmed to support divide ratios from 2 to 32767. Divide ratios less than

2 are prohibited.

Divide Ratio

Aux R_CNTR[14:0]

14

13

12

11

10

9876543210

2

000000000000010

3

000000000000011

•

•••••••••••••••

32767

111111111111111

2.4.2 PD_POL Aux

AUXILIARY SYNTHESIZER PHASE DETECTOR POLARITY

Aux R[17]

The PD_POL Aux bit is used to control the Aux synthesizer’s phase detector polarity based on the VCO tuning characteristics.

Control Bit

Register Location

Description

Function

01

PD_POL Aux

Aux R[17]

Aux Phase Detector

Polarity

Aux VCO Negative

Tuning

Characteristics

Aux VCO Positive

Tuning

Characteristics

Aux VCO Characteristics

20022609

2.4.3 ID

AUXILIARY SYNTHESIZER CHARGE PUMP CURRENT GAIN

Aux R[18]

The ID

Control Bit

Register Location

Description

Function

01

ID

Aux R[18]

Aux Charge Pump

Current Gain

LOW

0.95 mA

HIGH

3.80 mA

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