INA821 High-Precision Instrumentation Amplifier Texas Instruments INA821 High-Precision Instrumentation Amplifier offers low power consumption and operates over a wide single or dual-supply range. A single external resistor sets any gain from 1 to 10,000. The device has high precision due to super-beta input transistors, which provide low input offset voltage, offset voltage drift, input bias current, and input voltage and current noise. Additional circuitry protects the inputs against overvoltage up to ±40V.