AD736JR

Overview

The AD736JR is a low-power, precision monolithic true RMS-to-DC converter manufactured by Analog Devices Inc. It features laser trimming for high accuracy, with a maximum error of ±0.3mV ±0.3% of reading on sine wave inputs. The device operates within a wide supply voltage range of +2.8V to +16.5V and -3.2V to -16.5V, consuming a maximum supply current of 200µA. It utilizes an 8-pin SOIC package and supports signal crest factors up to 5. The internal architecture includes an input amplifier, full-wave rectifier, RMS core, and output buffer, enabling precise conversion of AC and DC input voltages into proportional DC outputs.

Feature Summary

• Laser-trimmed precision ensures minimal measurement error across diverse input waveforms including pulses and phase-controlled sine waves.
• Integrated output buffer amplifier provides design flexibility without requiring external trimming for specified accuracy.
• Low power consumption allows operation in battery-powered applications while maintaining high input impedance.
• Capable of calculating the RMS value of both AC and DC input signals with optional AC coupling via external capacitor.

Applications

• Portable digital multimeters
• Battery-powered measurement instruments
• Precision rectifier circuits replacing non-RMS designs
• Signal analysis for variable duty cycle pulses

Procurement Notes

Verify the specific suffix (e.g., JR vs JRZ) against the manufacturer's current datasheet to confirm package type and environmental compliance status. Ensure the selected variant matches the required operating temperature range and pinout configuration for your PCB layout. Cross-reference ordering information directly with Analog Devices or authorized distributors to confirm availability and lead times.

Selection Notes

Select this component when high accuracy is required for non-sinusoidal waveforms compared to average-responding meters. Consider the wide supply voltage range and low quiescent current for portable designs. Verify that the input signal amplitude and frequency fall within the specified operational limits for optimal performance. Evaluate the need for external filtering capacitors based on the desired response time and noise rejection requirements.

Part Context

The AD736 belongs to a family of true RMS-to-DC converters designed for precision analog signal processing. It replaces traditional averaging converters to eliminate errors associated with complex waveforms. The device integrates the mathematical operations of squaring, averaging, and square-rooting on a single silicon chip, offering a compact solution for accurate voltage measurements in industrial and scientific instrumentation.

Replacement Considerations

Check for direct pin-compatible alternatives such as the AD737 if higher bandwidth is required. Verify functional equivalence with other monolithic RMS converters from Analog Devices or competitors, ensuring matching accuracy, supply voltage ranges, and package dimensions before substitution.