April 2008

Rev 2

1/7

7

STPAC01F2

IPAD™, RF detector for power amplifier control

Features

– one for the signal detection

– one for the temperature compensation

Benefit

front-end designer to save PCB area and to

drastically reduce parasitic inductances.

Applications

Target applications are cellular phones and PDA

using GSM, DCS, PCS, AMPS, TDMA, CDMA

and 800 MHz to 1900 MHz frequency ranges.

Description

The STPAC01F2 is an integrated RF detector for

the power control stage. It converts RF signal

coming from the coupler into a DC signal usable

by the digital stage. It is based on the use of two

similar diodes, one providing the signal detection

while the second one is used to provide

temperature information to a thermal

compensation stage. A biasing stage suppresses

the detection diode drop voltage effect.

Figure 1.

Pin layout (bump side)

Figure 2.

Functional diagram

TM: IPAD is a trademark of STMicroelectronics.

Flip Chip

(8 bumps)

Gnd1

RFin

Gnd1

Gnd1

Gnd2

Bias

DC

out

V

Temp

32

1

A

B

C

Coupler

GND2

GND1

STPAC01F2

RF input

Thermal

compensation

Low pass

filter

RF detector

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