ADA4638-1ACPZ-R7

Overview

The ADA4638-1ACPZ-R7 is a single-channel, high-voltage precision zero-drift operational amplifier manufactured by Analog Devices Inc. It operates on single supplies from 4.5 V to 30 V or dual supplies from ±2.25 V to ±15 V. Key electrical specifications include a maximum input offset voltage of 14.5 μV and an offset drift of 0.1 μV/°C in the LFCSP package. The device features a gain-bandwidth product of 1.5 MHz, a slew rate of 1.5 V/μs, and a supply current of 0.95 mA maximum. It offers rail-to-rail output swing, 142 dB typical CMRR, and 143 dB typical PSRR.

Feature Summary

• Utilizes a patented ping-pong combination of auto-zeroing and chopping techniques to minimize low-frequency noise and eliminate 1/f noise components.
• Features rail-to-rail output capability with no output phase reversal when inputs remain within supply voltages.
• Provides ultralow input offset voltage and drift over the extended industrial temperature range.
• Includes internal ESD protection diodes connected between inputs and supply rails.

Applications

• Electronic weigh scales
• Pressure and position sensors
• Strain gage amplifiers
• Medical instrumentation
• Thermocouple amplifiers

Procurement Notes

Verify the specific package type (LFCSP) and reel packaging suffix against official manufacturer documentation before procurement. Confirm that the exposed pad connection requirements are met during assembly. Ensure compatibility with the intended supply voltage range and load conditions specified in the datasheet electrical characteristics tables.

Selection Notes

Select this component for applications requiring high DC accuracy and minimal drift over wide temperature ranges. Consider the 1.5 MHz bandwidth and 1.5 V/μs slew rate for signal conditioning needs. Evaluate the 0.95 mA supply current for power-constrained designs. Verify that the rail-to-rail output meets the system's dynamic range requirements without phase reversal issues.

Part Context

The ADA4638-1 belongs to Analog Devices' Zero-Drift Op Amp portfolio, designed for high-precision applications where large error sources cannot be tolerated. It is available in 8-lead SOIC and LFCSP packages. The device is specified for the extended industrial temperature range of −40°C to +125°C, ensuring reliable performance in demanding environments.

Replacement Considerations

Consult official Analog Devices documentation for confirmed substitute part numbers. Cross-reference pin configurations and electrical specifications carefully when considering alternatives.

FAQ

Does the ADA4638-1 exhibit output phase reversal?

No, the ADA4638-1 is designed to prevent output phase reversal provided that both inputs are maintained within the supply voltages.

What is the input common-mode voltage range?

The input common-mode voltage range includes the lower supply rail.

How does the ADA4638-1 handle low-frequency noise?

It uses a patented combination of auto-zeroing and chopping to eliminate 1/f noise and reduce noise energy at the chopping and auto-zeroing frequencies.