LMV242x 450MHz to 2GHz, 50dB, Log RF Power Detectors With PA Control Outputs

1 Features

• 450MHz to 2GHz operation

• 50dB log RF detector

• Integrated ramp filter

• External loop compensation option

• Accurate temperature compensation

• Shutdown mode for power save in RX slot

• GPRS compliant

• Support of InGaP HBT, bipolar technology

• WSON package: 3mm × 3mm

2 Applications

• GSM, GPRS, TDMA, TD-SCDMA mobile phone

• Pulse RF control

• Wireless LAN

• GSM and GPRS power amplifier module

• Transmit module

3 Description

The LMV2421 and LMV242 (LMV242x) are single-

output

and

dual-output

power

amplifier

(PA)

controllers. These devices are intended for use within

an RF transmit power control loop for RF PA control,

and in GSM and GPRS mobile phones. The LMV242x

support all single-supply PAs, including InGaP, HBT,

and bipolar power amplifiers. The devices operate

with a single supply from 2.6V to 5.5V.

Included in the LMV2421 PA controller are a log

RF detector, a ramp filter, and an output driver that

functions as an error amplifier.

The dual-output LMV242 includes two selectable

output drivers for control of two different PAs. The

LMV2421 input interface consists of two analog

and one digital inputs; two digital inputs for the

LMV242. The analog inputs are the RF input and

the ramp voltage input. The digital inputs perform

the function of Shutdown/Transmit Enable and Band

Select (LMV242 only). The LMV242x is active when

TX_EN = high. When TX_EN = low, the device is

in a low-power-consumption shutdown mode. During

shutdown, the outputs are pulled low to the minimum

output voltage. The Band Select (LMV242 only)

function enables either of two outputs, namely OUT1

when BS = high, or output OUT2 when BS = low.

The output that is not enabled is pulled low to the

minimum output voltage. Individual PA characteristics

are accommodated by a user-selectable external RC

combination.

The LMV242x are offered in a 10-lead WSON

package. The LMV242x are an excellent choice for

small-footprint, PA modules systems.

Device Information

PART NUMBER

CHANNEL COUNT

PACKAGE(1)

LMV2421

Single

NGY (WSON, 10)

3mm × 3mm(2)

LMV242

Dual

(1)

For more information, see Section 10.

(2)

The package size (length × width) is a nominal value and

includes pins, where applicable.

RF2

RF1

PA1

PA2

1

2

9

3

6

7

10

8

4

5

RFIN

VDD

GND

BS

TX_EN

VRAMP

COMP2

COMP1

LMV242

COUPLER

SWITCH

ANTENNA

OUT1

OUT2

50Ω

RF

PA

1

2

9

3

6

7

10

8

4

5

RFIN

VDD

GND

GND

TX_EN

VRAMP

COMP2

COMP1

LMV2421

COUPLER

ANTENNA

NC

OUT

50Ω

Typical Applications

LMV242, LMV2421

SNWS014D – MARCH 2004 – REVISED JUNE 2025

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.