Transmitter Functional Description

The simplified block diagram below shows the doubler and voltage regulator for an external transmit gain stage.

Function Register Programming Description (F-Latch)

If the control bits are “1X”, data is transferred from the 20-bit shift register into the 18-bit F-latch. Serial data format is shown

below.

MSB

REGISTER’S BIT MAPPING

LSB

19

18

17

16

15

14

13

12

11

10

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MODE CONTROL WORD

C2

C1

F18

F17

F16

F15

F14

F13

F12

F11

F10

F9

F8

F7

F6

F5

F4

F3

F2

F1

X

1

Note: X = Don’t Care Condition

Various modes of operation can be programmed with the function register bits F1–F18, including the phase detector polarity,

F11 and F12.

Mode

Control

Bit

Model Control Description

Setting to

“0” to Select

Setting to

“1” to Select

F1

Prescaler modules select.

32/33

64/65

F2

Phase detector polarity. It is used to reverse the polarity of

the phase detector according to the VCO characteristics.

Negative VCO

Characteristics

Positive VCO

Characteristics

F3

Charge pump current gain select.

LOW Charge Pump

Current (1X I

HIGH Charge Pump

Current (4X I

F4

TRI-STATE charge pump output.

Normal Operation

Force to TRI-STATE

F5

Reserved. Setting to “0” always.

—

—

F6

Receive chain power down control. Software power down

can only be activated when both F11 and F12 are set to “0”.

Power Up RX Chain

Power Down RX Chain

F7

Transmit chain power down control. Software power down

can only be activated when both F11 and F12 are set to “0”.

Power Up TX Chain

Power Down TX Chain

F8

Out 0 CMOS output.

OUT 0 = LOW

OUT 0 = HIGH

F9

Out 1 CMOS output. Functions only in software power down

mode, when both F11 and F12 are set to “0”.

OUT 1 = LOW

OUT 1 = HIGH

F10

Out 2 CMOS output. Functions only in software power down

mode, when both F11 and F12 are set to “0”.

OUT 2 = LOW

OUT 2 = HIGH

F11

F12

Power down mode select.

Set both F11 and F12 to “0” for software power down mode.

Set both F11 and F12 to “1” for hardwire power down mode.

Other combinations are reserved for test mode.

Software

Power Down

Hardware

Power Down

F13

Demodulator gain select

1X Gain Mode

3X Gain Mode

F14

Demodulator DC level shift +/− level shifting polarity

Set Negative Polarity

Set Positive Polarity

DS012815-6

Note: The transmitter can be powered down, either by hardware through the Tx PD pin, or by software through the programming of F7 bith in F-Latch. The

power down control method is determined by the settings of F11 and F12 in F-Latch. (Refer to Function Register Programming Description section for details.)

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