4

LTC4403-1/LTC4403-2

4403f

GND (Pin 4/5): System Ground.

PCTL (Pin 5/6): Analog Input. The external power control

DAC drives this input. The amplifier servos the RF power

until the RF detected signal equals the DAC signal applied

at this pin.

SHDN (Pin 6/7): Shutdown Input. A logic low on the SHDN

pin places the part in shutdown mode. A logic high enables

the part after 10

µs. SHDN has an internal 150k pull-down

resistor to ensure that the part is in shutdown when no input

via a 112

Ω resistor.

(LTC4403-1/LTC4403-2)

PI FU CTIO S

EDGE modulation.

resistor to ground.

RF (Pin 8/10): Coupled RF Feedback Voltage . This input

2400MHz. This pin has an internal 250

Ω termination, an

internal Schottky diode detector and peak detector

capacitor.

BLOCK DIAGRA

(LTC4403-2)

–

+

RFDET

–

+

GM

70mV

270kHz

FILTER

–

+

30k

22k

51k

30k

250

Ω

28pF

0.4pF

±0.05pF

12

Ω

100

Ω

100

Ω

4403 BD

12

Ω

150k

150k

150k

BSEL

PB

PA

60

µA60µA

RF

10

Li-Ion

1

GND

9

PCTL

6

RF PA

850MHz/900MHz

AZ

AUTOZERO

TXENB

TXENB

+

–

+

–

MUX

CONTROL

8

7

SHDN

RF PA

DIPLEXER

1.8GHz/1.9GHz

5

50

Ω

9

µs

DELAY

GAIN

COMPRESSION

2

3

BUFFER

38k

+

–

4