AD536AJQ (ANALOG DEVICES)

The AD536AJQ is a Complete Monolithic IC that performs true RMS-to-DC conversion. It offers performance comparable or superior to that of hybrid or modular units costing much more. The AD536A directly computes the true RMS value of any complex input waveform containing AC and DC components. A crest factor compensation scheme allows measurements with 1% error at crest factors up to 7. The wide bandwidth of the device extends the measurement capability to 300kHz with less than 3dB errors for signal levels greater than 100mV. An important feature of the AD536A, not previously available in RMS converters, is an auxiliary dB output pin. The logarithm of the RMS output signal is brought out to a separate pin to allow the dB conversion, with useful dynamic range of 60dB. Using an externally supplied reference current, the 0dB level can be conveniently set to correspond to any input level from 0.1V to 2V RMS.