Data Sheet

Conexant

Doc. No. 100774B

Proprietary Information and Specifications are Subject to Change

September 7, 2000

RF142

Heterojunction Bipolar Transistor Power Amplifier Dual-Band Controller

for GSM and PCS Applications

The RF142 Power Amplifier (PA) controller is a highly integrated, monolithic device

optimized for use in 900 MHz, 1800 MHz, and 1900 MHz Global System For

applications. The control current output from the RF142 can be used to control the

transmit power of a dual or multi-band Heterojunction Bipolar Transistor (HBT) PA.

The device consists of two sections: an RF detector, and a gain controller. The

RF142, when combined with a PA and a coupler, forms a closed PA control loop,

where the PA output power is controlled by a single analog reference voltage,

typically supplied by the baseband.

The RF142 device package and pin configuration are shown in Figure 1. The signal

pin assignments and functional pin descriptions are specified in Table 1. An RF142

block diagram is shown in Figure 2.

Features

• RF PA controller for use with HBT PAs

• 50 dB detector dynamic range

• Broadband, logarithmic power detector (800 MHz

to 2000 MHz)

• Logarithmic RF power detector requires no

external diodes

• Integrator and gain shaping block enhance loop

stability and linearity

• Three-cell battery operation (2.7 V to 5.0 V)

• Standby mode with 20 µA of current consumption

•

20-pin Thin Shrink Small Outline Package

(TSSOP)

Applications

•

Transmit power control for dual or multi-band

GSM digital cellular handsets

100774A-1_090700

GND1

VREF

VMP

VAPC+

VAPC-

ENABLE

RFPC+

RFPC-

GND2

VCC1

1

2

3

4

5

6

7

8

9

10

VPCGSM

VPCDCS

VCC2

BAND

AUX-

AUX+

CAP-

CAP+

NC

NC

18

17

16

15

14

13

12

11

19

20

Figure 1. RF142 Pin Configuration – 20-Pin TSSOP