AD737KRZ

Overview

The AD737KRZ is a low power, precision, monolithic true RMS-to-DC converter manufactured by Analog Devices Inc. It operates within a wide supply voltage range of ±2.5 V to ±16.5 V and features a typical standby current of 25 µA. The device provides high accuracy with a maximum error of ±0.2 mV ± 0.3% of reading for sine wave inputs. It supports signal crest factors up to 5 and offers direct interfacing with 3½ digit CMOS ADCs. The component is housed in an SOIC-8 package.

Feature Summary

• Computes true RMS values for various input waveforms including variable duty cycle pulses
• Provides average rectified value and absolute value outputs
• Features high input impedance and low input bias current
• Requires no external trims for specified accuracy

Applications

• Upgrading performance of non-RMS precision rectifiers
• Direct interfacing with 3½ digit CMOS ADCs
• Measurement of triac phase controlled sine waves

Procurement Notes

Verify the specific suffix 'KRZ' against official Analog Devices documentation to confirm temperature grade and packaging details. Ensure compatibility with system requirements regarding the negative-going output characteristic. Confirm RoHS compliance status through the manufacturer's latest datasheet or certification documents before integration.

Selection Notes

Select this component when precise RMS conversion is required for complex waveforms beyond simple sine waves. Consider the negative output polarity and ensure subsequent circuitry can accommodate it. Evaluate the need for input scaling if signals exceed the 200 mV full-scale range. Compare power consumption requirements against the typical 25 µA standby current specification.

Part Context

The AD737 series represents a family of true RMS-to-DC converters designed for cost-effective and low-power applications. The AD737KRZ variant specifically denotes the industrial temperature range version packaged in SOIC-8. It serves as a precision alternative to discrete solutions, offering laser-trimmed accuracy without external adjustments.

Replacement Considerations

The AD736 is a positive output-going version of the same basic device. Verify if the system requires a positive output signal, in which case the AD736 may be a suitable functional substitute.