The AD8361 is a mean-responding power detector for use in high frequency receiver and transmitter signal chains, up to 2.5 GHz. It is very easy to apply. It requires a single supply only between 2.7 V and 5.5 V, a power supply decoupling capacitor, and an input coupling capacitor in most applications. The output is a linear-responding dc voltage with a conversion gain of 7.5 V/V rms. An external filter capacitor can be added to increase the averaging time constant.The AD8361 is intended for true power measurement of simple and complex waveforms. The device is particularly useful for measuring high crest-factor (high peak-to-rms ratio) signals, such as CDMA and W-CDMA. The AD8361 has three operating modes to accommodate a variety of analog-to-digital converter requirements:Ground reference mode, in which the origin is zero.Internal reference mode, which offsets the output 350 mV above ground.Supply reference mode, which offsets the output to VS/7.5.The AD8361 is specified for operation from −40°C to +85°C and is available in 8-lead MSOP and 6-lead SOT-23 packages. It is fabricated on a proprietary high fTsilicon bipolar process.