The LMH2120 is a 40 dB Linear RMS power detector particularly suited for accurate power
measurement of modulated RF signals that exhibit large peak-to-average ratios, i.e, large
variations of the signal envelope. Such signals are encountered in W-CDMA and LTE cell phones. The
RMS measurement topology inherently ensures a modulation insensitive measurement.
The device has an RF frequency range from 50 MHz to 6 GHz. It provides an accurate,
temperature and supply insensitive, output voltage that relates linearly to the RF input power in
volt. The LMH2120's excellent conformance to a linear response enables an easy integration by using
slope and intercept only, reducing calibration effort significantly. The device operates with a
single supply from 2.7V to 5V. The LMH2120 has an RF power detection range from -35 dBm to 5 dBm
and is ideally suited for use in combination with a directional coupler. Alternatively, a resistive
divider can be used.
The device is active for EN = High, otherwise it is in a low power consumption shutdown
mode. To save power and prevent discharge of an external filter capacitance, the output (OUT) is
high impedance during shutdown.
The LMH2120 power detector is offered in a tiny 6-bump DSBGA package.