The AD622 is a low-cost, moderately accurate instrumentation amplifier that requires only one external resistor to set any gain between 2 and 1000. It features good DC performance, noise, and AC characteristics, making it suitable for a wide range of applications, including transducer interfaces, low-cost thermocouple amplifiers, industrial process controls, difference amplifiers, and low-cost data acquisition.
The AD622 is a low‑cost, moderately accurate instrumentation amplifier that requires only one external resistor to set any gain from 1 to 1000. It provides unity‑gain operation without an external resistor and optional gains with a single resistor, delivering low input offset voltage, low bias current, and excellent common‑mode rejection.
Typical applications include thermocouple amplification, transducer interfaces, industrial process controls, and data‑acquisition systems. The device operates from a wide supply range (+2.6 V to +15 V), consumes less than 1.5 mA, and maintains performance over –40 °C to +85 °C.
| Gain Range | 1 – 1000 |
|---|---|
| Gain Error (G=1) | 0.05 – 0.15 % |
| Input Offset Voltage | 125 µV max |
| Input Bias Current | 5 nA max |
| Common‑Mode Rejection Ratio (G=1) | ≥ 66 dB |
| Bandwidth (G=10) | 800 kHz |
| Supply Voltage Range | +2.6 V to +15 V |
| Operating Temperature Range | –40 °C to +85 °C |
The AD622 can be programmed for a gain from 1 to 1000.
Gain is set by a single external resistor (Rg) connected between pins 1 and 8.
The maximum input offset voltage is 125 µV.
It operates from +2.6 V up to +15 V.