TABLE 1. Programmable Modes

C1

C2

R16

R17

R18

R19

R20

0

0

RF2 Phase

RF2 I

CPo

RF2 D

o

RF2 LD

RF2 F

o

Detector Polarity

TRI-STATE

0

1

RF1 Phase

RF1 I

CPo

RF1 D

o

RF1 LD

RF1 F

o

Detector Polarity

TRI-STATE

C1

C2

N19

N20

1

0

RF2

Pwdn

Prescaler

RF2

1

1

RF1

Pwdn

Prescaler

RF1

TABLE 2. Mode Select Truth Table

Phase Detector

D

I

CPo

RF1

RF2

Pwdn

Polarity (Note 9)

(Note 7)

(Note 8)

Prescaler

Prescaler

(Note 7)

0

Negative

Normal Operation

LOW

64/65

64/65

pwrd up

1

Positive

TRI-STATE

HIGH

128/129

128/129

pwrd dn

Note 7: Refer to POWERDOWN OPERATION in Functional Description.

Note 9: PHASE DETECTOR POLARITY

Depending upon VCO characteristics, the R16 bits should be set accordingly:

When VCO characteristics are positive like (1), R16 should be set HIGH;

When VCO characteristics are negative like (2), R16 should be set LOW.

VCO Characteristics

DS012807-8

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