A power detector with a detection signal input connectable to a source of a radio frequency signal and a detected power level output has a differential amplifier detector circuit with an input connected to the detection signal input and an output corresponding to the detected power level output. A feedback network is connected to the input and the output of the differential amplifier detector circuit. A mirror circuit is connected to the differential amplifier detector circuit. A root mean square current corresponding to a power level of the radio frequency signal from the source is mirrored and integrated, with a direct current voltage level being generated therefrom and output to the detected power level output.