LMH2120UM Linear RMS Power Detector With 40 DB Dynamic Range Ic

LMH2120UM Linear RMS Power Detector with 40 dB Dynamic Range ic

APPLICATION INFORMATION

The LMH2120 is a 40 dB Linear RMS power detector particularly suited for accurate power measurements of
modulated RF signals that exhibit large peak-to-average ratios (PAR’s). The RMS detector implements the exact
definition of power resulting in a power measurement insensitive to high PAR’s. Such signals are encountered,
e.g, in LTE and W-CDMA applications. The LMH2120 has an RF frequency range from 50 MHz to 6 GHz. It
provides an output voltage that relates linearly to the RF input power in volt. Its output voltage is highly
insensitive to temperature and supply variations.

TYPICAL APPLICATION
The LMH2120 can be used in a wide variety of applications like LTE, W-CDMA, CDMA and GSM. This section
discusses the LMH2120 in a typical transmit power control loop for such applications.
Transmit-power-control-loop circuits make the transmit-power level insensitive to power amplifier (PA)
inaccuracy. This is desirable because power amplifiers are non-linear devices and temperature dependent,
making it hard to estimate the exact transmit power level. If a control loop is used, the inaccuracy of the PA is
eliminated from the overall accuracy of the transmit power level. The accuracy of the transmit power level now
depends on the RF detector accuracy instead. The LMH2120 is especially suited for transmit-power control
applications, since it accurately measures transmit power and is insensitive to temperature, supply voltage and
modulation variations.

Applications:

Multi Mode, Multi Band RF Power Control
GSM/EDGE
– CDMA/CDMA2000
– W-CDMA
– OFDMA
– LTE
Infrastructure RF Power Control

Microcontroller IC (MCU) and processor Specification :MSP430F5438AIPZR