2.2.1 R_CTR[9:0]

Reference Divider (R COUNTER)

R[10:1]

The reference divider can be programmed to support divide ratios from 2 to 1023. Divide ratios of less than 2 are prohibited.

R_CNTR [9:0]

Reference Divider Ratio

9876543210

2

0000000010

3

0000000011

•

••••••••••

1,023

1111111111

2.2.2 CP_TRI

Charge Pump TRI-STATE

R[11]

The CP_TRI control bit allows the charge pump to be switched between a normal operating mode and a high impedance output

state. This happens asynchronously or immediately with the change in CP_TRI bit.

Control Bit

Register Location

Description

Function

01

CP_TRI

R[11]

Charge Pump

TRI-STATE

Charge Pump Operates

Normal

Charge Pump Output

in High Impedance

State

2.2.3 PD_POL

Phase Detector Polarity

R[12]

The PD_POL control bit is used to set the polarity of the phase detector based on the VCO tuning characteristic.

Control Bit

Register Location

Description

Function

01

PD_POL

R[12]

Phase Detector

Polarity

Negative VCO Tuning

Characteristic

Positive VCO Tuning

Characteristic

VCO Characteristics

20038409

2.2.4 LD_OUT[1:0]

LD Output Select

R[14:13]

The LD_Out control word is used to select which signal is routed the the LD pin.

LD_OUT[1:0]

LD Pin Output Mode

Output Circuit

Configuration

0

Digital Lock Detect

Push-Pull

1

Analog Lock Detect

Open-Drain

2

R divider output

Push-Pull

3

N divider output

Push-Pull

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