ADI AD8420ARMZ

A low cost, micropower, wide supply range, instrumentation amplifier with a rail-to-rail output and a novel architecture that allows for extremely flexible design. It is optimized to amplify small differential voltages in the presence of large common-mode signals.

Based on an indirect current feedback architecture that gives it an excellent input common-mode range. Unlike conventional instrumentation amplifiers, it can easily amplify signals at or even slightly below ground without requiring dual supplies. It has rail-to-rail output, and the output voltage swing is completely independent of the input commonmode voltage.

Single-supply operation, micropower current consumption, and rail-to-rail output swing make it ideal for batterypowered applications. Its rail-to-rail output stage maximizes dynamic range when operating from low supply voltages. Dualsupply operation (±15 V) and low power consumption make it ideal for a wide variety of applications in medical or industrial instrumentation.

Available in an 8-lead MSOP package. Performance is specified over the full temperature range of -40°C to +85°C, and the device is operational from -40°C to +125°C.

• Maximum supply current: 90 μA
• Minimum CMRR: 100 dB
• Drives heavy capacitive loads: ~700 pF
• Rail-to-rail output
• Input voltage range goes below ground
• Gain set with 2 external resistors
• Can achieve low gain drift at any gain
• Very wide power supply range: Single supply: 2.7 V to 36 V; Dual supply: ±2.7 V to ±18 V
• Bandwidth (G = 100): 2.5 kHz
• Input voltage noise: 55 nV/Hz
• High dc precision: Maximum offset voltage: 125 μV; Maximum offset drift: 1 μV/°C
• Maximum differential input voltage: ±1 V
• 8-lead MSOP package

• Bridge amplifiers
• Pressure measurement
• Medical instrumentation
• Portable data acquisition
• Multichannel systems