2.5.1.2 RF_A[4:0] - LMX2434 RF Synthesizer Swallow Counter (A Counter) (R1[7:3])

The LMX2434 A counter is a 5-bit swallow counter used in the programmable feedback divider. The RF_A control word can be

programmed to values ranging from 0 to 31.

Divide Ratio

LMX2434

RF_A[4:0]

4321

0

0

0000

0

1

0000

1

•

••••

•

31

1111

1

2.5.2 LMX243x RF Synthesizer Programmable Binary Counter

2.5.2.1 RF_B[14:0] - LMX2430/33 RF Synthesizer Programmable Binary Counter (B Counter) (R1[21:7])

The RF_B control word is used to setup the RF synthesizer’s B counter. For both the LMX2430 and LMX2433, the B counter is

a 15-bit programmable binary counter used in the programmable feedback divider. The RF_B control word can be programmed

to values ranging from 3 to 32767. Divide ratios less than 3 are prohibited.

Divide

Ratio

LMX2430/33

RF_B[14:0]

14

13

12

11

10

987654321

0

3

00000000000001

1

4

00000000000010

0

•

••••••••••••••

•

32767

11111111111111

1

2.5.2.2 RF_B[13:0] - LMX2434 RF Synthesizer Programmable Binary Counter (B Counter) (R1[21:8])

The LMX2434 B counter is a 14-bit programmable binary counter used in the programmable feedback divider. The RF_B control

word can be programmed to values ranging from 3 to 16383. Divide ratios less than 3 are prohibited.

Divide

Ratio

LMX2434

RF_B[13:0]

13

12

11

10

987654321

0

3

0000000000001

1

4

0000000000010

0

•

•••••••••••••

•

16383

1111111111111

1

2.5.3 LMX243x RF Synthesizer Prescaler Select

2.5.3.1 RF_P - LMX2430/33 RF Synthesizer Prescaler Select (R1[22])

Both the LMX2430 and LMX2433 RF synthesizers utilize a selectable dual modulus prescaler. An 8/9 or a 16/17 prescale ratio

can be selected.

Control Bit

Register Location

Description

Function

01

RF_P

R1[22]

LMX2430/33

RF Prescaler Select

8/9 Prescaler

Selected

16/17 Prescaler

Selected

2.5.3.2 RF_P - LMX2434 RF Synthesizer Prescaler Select (R1[22])

The LMX2434 RF synthesizer utilizes a selectable dual modulus prescaler. A 16/17 or a 32/33 prescale ratio can be selected.

Control Bit

Register Location

Description

Function

01

RF_P

R1[22]

LMX2434

RF Prescaler Select

16/17 Prescaler

Selected

32/33 Prescaler

Selected

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