50 MHz to 3.5 GHz 40 dB Logarithmic Power Detector for CDMA and WCDMA

The LMV221 is a 40-dB RF power detector intended for use in CDMA and WCDMA applications. The device has an RF frequency range from 50 MHz to 3.5 GHz. It provides an accurate temperature and supply-compensated output voltage that relates linearly to the RF input power in dBm. The circuit operates with a single supply from 2.7 V to 3.3 V.

The LMV221 has an RF power detection range from −45 dBm to −5 dBm and is ideally suited for direct use in combination with a 30-dB directional coupler. Additional low-pass filtering of the output signal can be achieved by means of an external resistor and capacitor. shows a detector with an additional output low pass filter. The filter frequency is set with RS and CS.

shows a detector with an additional feedback low pass filter. Resistor RP is optional and lowers the trans-impedance gain (RTRANS). The filter frequency is set with CP//CTRANS and RP//RTRANS.

The device is active for Enable = 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.

For all available packages, see the orderable addendum at the end of the data sheet.