ADI AD8422ARZ

The AD8422 is a high precision, low power, low noise, rail-to-rail instrumentation amplifier with the industry's best performance per microamp. The device handles signals with ultralow distortion, with load having no effect on performance across the entire output range. It employs the latest process and design techniques to achieve higher dynamic range and lower errors than previous generations, while consuming less than one-third the power. The AD8422 uses the same high performance pinout as the AD8221. The AD8422 features extremely low bias current, eliminating errors at high source impedances and allowing multiple sensors to be multiplexed to the inputs. Its low voltage noise and low current noise make the AD8422 an ideal choice for measuring Wheatstone bridges. The wide input range and rail-to-rail output of the AD8422 deliver the full benefits of a high performance instrumentation amplifier in single-supply applications. Whether operating from high or low supply voltages, the AD8422's power-saving characteristics make it an excellent choice for high channel count or power-sensitive applications, while still meeting the tight error budgets typical of such applications. The AD8422 features robust input overvoltage protection for assured stability without compromising noise performance. It offers high ESD immunity and continuous input voltage protection of up to 40 V from the opposite supply rail. Gain can be set from 1 to 1000 with a single resistor. The reference pin can be used to apply a precise offset to the output voltage. The AD8422 is rated for operation over the -40°C to +85°C temperature range, with typical performance curves guaranteed up to 125°C, and is available in 8-lead MSOP and SOIC packages.

• Low power: quiescent current 330 μA (max)
• Rail-to-rail output
• Low noise, low distortion: maximum input voltage noise 8 nV/√Hz at 1 kHz, RTI noise: 0.15 μV p-p (G = 100), nonlinearity with 2 kΩ load: 0.5 ppm (G = 1)
• Excellent AC performance: CMRR at 7 kHz: 80 dB (min, G = 71), bandwidth: 2.2 MHz (G = 7)
• High accuracy DC performance (AD8422BRZ): CMRR: 150 dB (min, G = 1000), gain error: 0.04% (max, G = 1000), input offset drift: 0.3 μV/°C (max), input bias current: 0.5 nA (max)
• Wide supply voltage range: 3.6 V to 36 V single supply, ±1.8 V to ±18 V dual supply
• Input overvoltage protection: 40 V, reverse supply protection
• Gain range: 1 to 1000

• Medical instruments
• Industrial process control
• Strain gauges
• Sensor interfaces
• Precision data acquisition systems
• Channel-isolated systems
• Portable instrumentation