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  2. Amplifiers
  3. Operational Amplifiers (Op Amps)
  4. Zero-Drift Op Amps
  5. ADA4638-1


Features and Benefits

  • Single Supply Operation: 4.5 V to 30V
  • Dual supply operation: ±2.25 V to ±15 V
  • Low offset voltage: 4 μV maximum
  • Input offset voltage drift: 0.05 μV/°C maximum
  • High gain: 130 dB minimum
  • High PSRR: 120 dB minimum
  • High CMRR: 130 dB minimum
  • Input common-mode range includes lower supply rail
  • Rail-to-rail output
  • Low supply current: 0.95 mA maximum

Product Details

The ADA4638-1 is a high voltage, high precision, zero-drift amplifier featuring rail-to-rail output swing. It is guaranteed to operate from 4.5 V to 30 V single supply or ±2.25 V to ±15 V dual supplies while consuming less than 0.95 mA of supply current at ±5 V.

With an offset voltage of 4 μV, offset drift less than 0.05 μV/°C, no 1/f noise, and input voltage noise of only 1.2 μV p-p (0.1 Hz to 10 Hz), the ADA4638-1 is suited for high precision applications where large error sources cannot be tolerated. Pressure sensors, medical equipment, and strain gage amplifiers benefit greatly from nearly zero drift over the wide operating temperature range. Many applications can take advantage of the rail-to-rail output swing provided by the ADA4638-1 to maximize the signal-to-noise ratio (SNR).

The ADA4638-1 is specified for the extended industrial (−40°C to +125°C) temperature range and is available in 8-lead LFCSP (3 mm × 3 mm) and SOIC packages.


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

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (1)

Tools & Simulations

SPICE Models

Design Tools

Analog Filter Wizard

Use the Analog Filter Wizard to design low-pass, high-pass, or band-pass filters with actual op amps in minutes. As you progress through the design process, you can observe the characteristics of your filter design from ideal specifications to real world circuit behavior. Quickly evaluate the tradeoffs in op amp specifications - including gain-bandwidth, noise, and supply current – to determine the best filter design for your requirements.

Analog Photodiode Wizard

Use Photodiode Wizard to design a transimpedance amplifier circuit to interface with a photodiode. Select a photodiode from the library included in the tool, or enter custom photodiode specifications. Quickly observe tradeoffs between Bandwidth, Peaking (Q), and ENOB/SNR. Modify circuit parameters, and immediately see results in plots for pulse response, frequency response, and noise gain.

Reference Designs (1)

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
ADA4638-1ACPZ-R7 Material Declaration Reliability Data 8-Lead LFCSP (3mm x 3mm w/ EP)
ADA4638-1ACPZ-RL Material Declaration Reliability Data 8-Lead LFCSP (3mm x 3mm w/ EP)
ADA4638-1ARZ Material Declaration Reliability Data 8-Lead SOIC
ADA4638-1ARZ-R7 Material Declaration Reliability Data 8-Lead SOIC
ADA4638-1ARZ-RL Material Declaration Reliability Data 8-Lead SOIC
Wafer Fabrication Data

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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.