DESCRIPTION

· The AD737 is a low power, precision, monolithic, true rms-to-dc converter.

· It is laser trimmed for maximum error of ±0.2 mV ± 0.3% of reading with sine wave inputs.

· It maintains high accuracy with a wide range of input waveforms, including variable duty cycle pulses and triac controlled sine waves.

· The AD737 computes the rms value of both ac and dc input voltages and is ac-coupled by adding an input capacitor.

· It is optimized for portable multimeters and other battery-powered applications, requiring only 160 μA of power supply current.

FEATURES

· Computes True rms value, average rectified value, and absolute value.

· Provides 200 mV full-scale input range (larger inputs with input scaling).

· Direct interfacing with 3½ digit CMOS analog-to-digital converters (ADCs).

· High input impedance: 10^12 Ω and low input bias current: 25 pA maximum.

· High accuracy: ±0.2 mV ± 0.3% of reading with signal crest factors up to 5.

· Wide power supply range: ±2.5 V to ±16.5 V and low power: 25 μA (typical) standby current.

· No external trims needed for specified accuracy.

APPLICATIONS

· Suitable for upgrading the performance of non-rms precision rectifiers in many applications.

· Ideal for portable multimeters and other battery-powered applications due to low power consumption.

· Compatible with high input impedance ADCs, making it useful in various measurement and monitoring systems.