ADA4638-1ACPZ-RL

Overview

The ADA4638-1ACPZ-RL is a single-channel, high-voltage precision zero-drift operational amplifier manufactured by Analog Devices Inc. It operates from 4.5 V to 30 V single supply or ±2.25 V to ±15 V dual supplies with a maximum supply current of 0.95 mA. Key electrical specifications include a maximum input offset voltage of 4 μV at 10 V and 4.5 μV at 30 V, an offset drift of 0.05 μV/°C (SOIC) or 0.08 μV/°C (LFCSP), and a gain-bandwidth product of 1.5 MHz. The device features rail-to-rail output swing, 142 dB typical CMRR, and low noise density of 66 nV/√Hz.

Feature Summary

• Utilizes a patented ping-pong combination of auto-zeroing and chopping techniques to eliminate 1/f noise and maintain ultralow offset voltage over temperature.
• Provides rail-to-rail output swing across the full operating voltage range to maximize signal-to-noise ratio.
• Features no output phase reversal when inputs are maintained within supply voltages.
• Offers high DC accuracy with minimum open-loop gain of 130 dB and high PSRR.

Applications

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

Procurement Notes

Verify the specific package variant against the datasheet outline dimensions, as the -ACPZ suffix denotes the LFCSP package. Confirm that the exposed pad connection requirements for thermal management and electrical grounding are addressed in the PCB layout design. Ensure input protection resistors are included if overvoltage conditions exceeding supply rails are possible to prevent ESD diode conduction damage.

Selection Notes

Select this component for applications requiring high DC precision without the need for external calibration due to its zero-drift architecture. It is suitable for high-voltage environments up to 30 V where rail-to-rail output dynamics are necessary. Consider the LFCSP package for compact designs but account for the exposed pad soldering requirements. Verify that the 1.5 MHz bandwidth meets the signal frequency requirements.

Part Context

The ADA4638-1 belongs to Analog Devices' Zero-Drift Op Amp portfolio, specifically designed for high-precision applications. It is part of the ADA4638 series, which includes variants like the AD8638 and ADA4528-1. The device is specified for the extended industrial temperature range of −40°C to +125°C and is available in 8-lead SOIC and LFCSP packages.

Replacement Considerations

Public confirmed substitute part numbers: ADA4638-1ARZ-R7, ADA4638-1ARZ, ADA4638-1ACPZ-RL.