2.3 R1 REGISTER

The R1 register contains the FREQ_OFF, RF_EN and OB_CRL control words. The register address bits are R1[1:0] = 01. The

detailed descriptions and programming information for each control word is discussed in the following sections.

Reg

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9876543210

MSB

SHIFT REGISTER BIT LOCATION

LSB

DATA[21:0]

ADDRESS

[1:0]

FIELD

R1

011010001010101001

OB_CRL

[1:0]

RF_

EN

FREQ_

OFF

01

2.3.1 FREQ_OFF - RF Synthesizer System Frequency Offset (R1[2])

The FREQ_OFF bit is used to offset the RF frequency by +5 kHz.

Control Bit

Register Location

Description

Function

01

FREQ_OFF

R1[2]

RF Synthesizer

System Frequency

Offset

RF Synthesizer

System Frequency

Offset Disabled

RF Synthesizer

System Frequency

Offset Enabled

2.3.2 RF_EN - RF Synthesizer System Enable (R1[3])

The RF_EN bit is used to switch the RF synthesizer system (PLL and VCO) between a powered up and powered down mode.

Control Bit

Register Location

Description

Function

01

RF_EN

R1[3]

RF Synthesizer

System Enable

RF Synthesizer

System Powered

Down

RF Synthesizer

System Active

2.3.3 OB_CRL[1:0] - RF VCO Output Buffer Power Control (R1[5:4])

The OB_CRL word is used to set the RF VCO output buffer power level. The power level can be set according to the system

requirements.

OB_CRL[1:0]

RF VCO Output Buffer Power Level

(dBm)

0

0

−4.5

0

1

−2.0

1

0

0.5

1

1

3.0

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