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 singleoutput
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.