1

LTC4403-1/LTC4403-2

4403f

Multiband RF Power

Controllers for EDGE/TDMA

The LTC

RF power amplifiers operating in the 300MHz to 2.4GHz

PA modules with two control inputs. An internal sample

and hold circuit enables the LTC4403-2 to be used with

AM modulation via the carrier or PA supply. The input

voltage range is optimized for operation from a single

lithium-ion cell or 3

× NiMH.

RF power is controlled by driving the RF amplifier power

control pins and sensing the resultant RF output power.

The RF sense voltage is peak detected using an on-chip

Schottky diode. This detected voltage is compared to the

DAC voltage at the PCTL pin to control the output power.

The LTC4403-1 is a single output RF power controller

with identical performance to the LTC4403-2. The

available in an 8-pin MSOP package.

Internal and external offsets are cancelled over tempera-

ture by an autozero control loop. The shutdown feature

disables the part and reduces the supply current to

<10

µA.

s

Supports AM Modulation in EDGE/TDMA (ANSI-136)

Applications

s

Single Output RF Power Amplifier Control

(LTC4403-1)

s

Dual Output RF Power Amplifier Control (LTC4403-2)

s

Internal Schottky Diode Detector with >40dB Range

s

Wide Input Frequency Range: 300MHz to 2.4GHz

s

Autozero Loop Cancels Offset Errors and

Temperature Dependent Offsets

s

s

Allows Direct Connection to Battery

s

RF Output Power Set by External DAC

s

Internal Frequency Compensation

s

Rail-to-Rail Power Control Outputs

s

Low Operating Current: 1mA

s

Low Shutdown Current: < 10

µA

s

PCTL Input Filter

s

Available in a 8-Pin MSOP Package (LTC4403-1)

and 10-Pin MSOP (LTC4403-2)

, LTC and LT are registered trademarks of Linear Technology Corporation.

LTC4403-2 Multiband EDGE Cellular Telephone Transmitter

s

Multiband GSM/GPRS/EDGE Cellular

Telephones

s

PCS Devices

s

Wireless Data Modems

s

U.S. TDMA Cellular Phones

BSEL

SHDN

PCTL

1

9

8

7

6

10

2

3

4

5

RF

GND

GND

LTC4403-2

0.4pF

± 0.05pF

Li-Ion

SHDN

BSEL

850MHz/

900MHz

DAC

RF PA

DIPLEXER

1.8GHz /

1.9GHz

RF PA

50

Ω

4403 TA01

0.1

µF

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO