2.7 R5 REGISTER

The R5 register contains the IF_R control word. The register address bits are R5[4:0] = 01111. Register R5 is active only when

the SPI_DEF bit in Register R0 is set to 0. Regsiter R5 should only be used to set the IF R counter if the default value is not

desired. The detailed description and programming information for this control word is discussed in the following section.

Reg

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9876543210

MSB

SHIFT REGISTER BIT LOCATION

LSB

DATA[18:0] FIELD

ADDRESS

[4:0]

FIELD

R5

0000000000

IF_R

[8:0]

01111

2.7.1 IF_R[8:0] - IF Synthesizer Programmable Reference Divider (R5[13:5])

The IF_R control word is used to setup the IF synthesizer’s reference divider. The IF_R control word can be programmed to

values ranging from 2 to 511. Divide ratios less than 2 are prohibited.

Divide Ratio

IF_R[8:0]

87654321

0

2

00000001

0

3

00000001

1

•

••••••••

•

511

11111111

1

2.8 R6 REGISTER

The R6 register is used for internal testing of the device and is not intended for customer use. The register address bits are

R6[5:0] = 011111. Register R6 is active only when the SPI_DEF bit in Register R0 is set to 0.

Reg

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9876543210

MSB

SHIFT REGISTER BIT LOCATION

LSB

DATA[17:0] FIELD

ADDRESS

[5:0]

FIELD

R6

000000011111111111

011111

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