The ADL5502 is a mean-responding (true rms) power detector in combination with an envelope detector to accurately determine the crest factor of a modulated signal. It can be used in high frequency receiver and transmitter signal chains from 450 MHz to 6 GHz with envelope bandwidths over 10 MHz. Requiring only a single supply between 2.5 V and 3.3 V, the detector draws less than 3 mA. The input is internally ac-coupled and has a nominal input impedance of 500 Ω.The rms output is a linear-responding dc voltage with a conversion gain of 1.8 V/V rms at 900 MHz. The peak envelope output with a conversion gain of 1.2 V/V is toggled for peak hold with less than 1% output voltage droop in over 1 ms.The ADL5502 is a highly accurate, easy to use means of determining the rms and peak to the average value of complex waveforms. It can be used for crest factor measurements of both simple and complex waveforms but is particularly useful for measuring high crest factor (high peak-to-rms ratio) signals, such as W-CDMA, CDMA2000, and QPSK-/QAM-based OFDM waveforms. The peak hold function allows the capture of short peaks in the envelope with lower sampling rate ADC’s.The crest factor detector operates from −40°C to +85°C and is available in an 8-ball, 1.5 mm × 1.5 mm wafer-level chip scale package. It is fabricated on a high fTsilicon BiCMOS process.ApplicationsPower and envelope measurement of W-CDMA, CDMA2000, and QPSK-/QAM-based OFDM, and other complex modulation waveformsRF transmitter or receiver power and envelope measurement