Description

The AD8629ARMZ is an instrumentation opamp that belongs to the AD8628/AD8629/AD8630 series of zero-drift amplifiers. It boasts ultra-low offset, drift, and bias current, with benefits previously found only in expensive auto-zeroing or chopper-stabilized amplifiers. Using Analog Devices’ topology, these zero-drift amplifiers combine low cost with high accuracy and low noise. Operation is fully specified from 2.7 V to 5 V single supply (±1.35 V to ±2.5 V dual supply).

Specifications and features

• Lowest auto-zero amplifier noise
• Low offset voltage: 1 μV
• Input offset drift: 0.002 μV/°C
• Rail-to-rail input and output swing
• 5 V single-supply operation
• High gain, CMRR, and PSRR: 120 dB
• Very low input bias current: 100 pA max
• Low supply current: 1.0 mA
• Overload recovery time: 10 μs
• No external components required

Application Scenarios

The AD8629ARMZ is useful in a range of applications, including automotive sensors, pressure and position sensors, strain gage amplifiers, medical instrumentation, thermocouple amplifiers, precision current sensing, and photodiode amplifiers.

Comparison

• Ultralow offset, drift, and bias current
• Wide bandwidth auto-zero amplifier
• Rail-to-rail input and output swings
• Low noise
• No external capacitor required
• Greatly reduces digital switching noise found in most chopper-stabilized amplifiers.

• None identified