AD737AN

Overview

The AD737AN is a low power, precision, monolithic true RMS-to-DC converter manufactured by Analog Devices. It computes the true RMS value of input signals with high accuracy across various waveforms, including variable duty cycle pulses and phase-controlled sine waves. The device features a wide power supply range from ±2.5 V to ±16.5 V and operates within a temperature range of -40°C to +85°C. It offers a maximum error of ±0.2 mV ± 0.3% of reading for sine wave inputs and maintains performance up to signal crest factors of 5. The component utilizes a PDIP-8 package and draws a typical standby current of 25 µA.

Feature Summary

• Computes true RMS values directly without external trims
• Maintains high accuracy across diverse input waveforms
• Features high input impedance and low bias current

Applications

• Upgrading non-RMS precision rectifier circuits
• Direct interfacing with 3½ digit CMOS ADCs
• Signal measurement in instrumentation systems

Procurement Notes

Verify availability status as distribution channels may indicate limited stock or special order requirements. Confirm RoHS compliance details and specific manufacturing lot dates upon request. Ensure the ordering suffix matches the required package type and temperature grade. Cross-reference the manufacturer part number with official datasheets to confirm pinout and electrical specifications before finalizing procurement.

Selection Notes

Select this component when precise RMS conversion is required for complex waveforms beyond simple sinusoids. Consider the negative-going output characteristic relative to the positive-output AD736 variant. Evaluate the low power consumption benefits for battery-operated or thermally constrained designs. Verify that the input scaling requirements align with the 200 mV full-scale input range capability.

Part Context

The AD737 belongs to the AD737 series of true RMS-to-DC converters. It serves as a cost-effective alternative to traditional precision rectifier circuits, offering superior accuracy and simplified design. The device is part of Analog Devices' specialized power management and signal processing portfolio, designed for applications demanding reliable analog computation.

Replacement Considerations

The AD736 is the positive-output version of the same basic device architecture. Verify output polarity requirements when substituting between these models. No other direct functional substitutes are confirmed in the provided documentation.