AD637JQ

Overview

The AD637JQ is a high-precision, wide-bandwidth RMS-to-DC converter manufactured by Analog Devices Inc. It computes the true RMS value of complex waveforms with a maximum nonlinearity of 0.02% for inputs between 0 V and 2 V RMS. The device supports crest factors up to 10 with less than 1% additional error. It offers a bandwidth of 8 MHz at 2 V RMS input and 600 kHz at 100 mV RMS input. The IC operates on dual supplies ranging from ±3 V to ±18 V, drawing a quiescent current of 2.2 mA, which can be reduced to 350 μA via chip select power-down. It is housed in a 14-pin CERDIP package.

Feature Summary

• Computes true RMS values of any complex waveform with high accuracy
• Includes crest factor compensation scheme for signals up to a crest factor of 10
• Features chip-select power-down capability for analog three-state operation and current reduction

Applications

• Precision signal measurement systems requiring true RMS conversion
• Audio and vibration analysis equipment
• Power monitoring and control circuits

Procurement Notes

Verify the specific suffix JQ indicates the commercial temperature range and CERDIP packaging configuration. Confirm availability status as distribution channels may list discontinued or limited stock items. Ensure supply chain sources provide original manufacturer documentation to validate authenticity and revision level before procurement.

Selection Notes

Select this component when high accuracy and wide bandwidth are required for RMS-to-DC conversion. It is suitable for applications involving complex waveforms where crest factor errors must be minimized. Consider the power-down feature if system energy efficiency is critical. Verify that the operating voltage range aligns with the available dual power supplies in the design.

Part Context

The AD637 belongs to a family of monolithic RMS-to-DC converters designed for performance comparable to discrete techniques. It integrates functions such as squaring, averaging, and square-rooting on a single chip. The JQ variant specifically denotes the ceramic dual in-line package version, offering robust construction for through-hole mounting in industrial environments.

Replacement Considerations

Public confirmed substitute part numbers: None.