This document describes the features and characteristics of the 30V zero-drift, rail-to-rail output precision amplifier ADA4638-1, including single supply and dual supply operation, low offset voltage and drift, high gain, high PSRR and CMRR, input common-mode range including lower supply rail, and rail-to-rail output.
The ADA4638-1 is a high‑voltage, zero‑drift precision amplifier with rail‑to‑rail output. It operates from a single 4.5 V to 30 V supply or dual +2.25 V to +15 V supplies, delivering low offset voltage and high gain for demanding applications such as weigh scales, pressure sensors, strain‑gage amplifiers, medical instrumentation, and thermocouple amplifiers.
The datasheet provides detailed electrical specifications, including offset voltage, bias currents, PSRR, gain, output swing, noise performance, and thermal resistance, as well as absolute maximum ratings and recommended PCB layout guidelines.
| Supply Voltage (single) | 4.5 V to 30 V |
|---|---|
| Supply Voltage (dual) | +2.25 V to +15 V |
| Offset Voltage | 4 pV max |
| Offset Voltage Drift | 0.05 pV/°C max |
| Gain | ≥130 dB |
| Power Supply Rejection Ratio (PSRR) | ≥120 dB |
| Absolute Maximum Supply Voltage | 33 V |
| Operating Temperature Range | ‑40 °C to +125 °C |
Typical applications include electronic weigh scales, pressure and position sensors, strain‑gage amplifiers, medical instrumentation, and thermocouple amplifiers.
The absolute maximum supply voltage rating is 33 V.