AD637BQ

The AD637BQ from Analog Devices is a complete, high-accuracy, RMS-to-DC converter designed to compute the true RMS value of any complex waveform. It offers performance comparable to discrete and modular techniques in accuracy, bandwidth, and dynamic range.

Key features include a maximum nonlinearity of 0.02% for inputs from 0 V to 2 V rms and a wide bandwidth of 8 MHz at 2 V rms input, extending to 600 kHz at 100 mV rms input. It can compute true RMS, mean square, or absolute value, providing an equivalent DC output voltage. Superior crest factor compensation allows measurements of signals with crest factors up to 10 with less than 1% additional error.

The device offers a 60 dB range for its dB output. A chip select/power-down feature allows for reduced quiescent current from 2.2 mA to 350 µA, facilitating use in low-power applications. When powered down, the output enters a high impedance state, enabling multiple AD637s to be connected for wideband true RMS multiplexer applications.

Packaged in a 14-CERDIP, the AD637BQ is designed for through-hole mounting. It operates with a voltage range of ±3V to 18V and typically draws 2.2 mA of quiescent current.