1 Features
• Gain-bandwidth product: 50-MHz
• High precision
– Input offset voltage: 95-μV (maximum)
– Offset drift: 1.2-μV/°C (maximum)
• Low power
– Quiescent current: 800-μA/ch (typical)
– Supply voltage: 2.7-V to 12.6-V
• Input voltage noise: 6.3-nV/√Hz
• Slew rate: 100-V/μs
• Rail-to-rail input and output
• HD2/HD3: –129 dBc/–138 dBc at 20 kHz (2-VPP)
• Operating temperature range:
–40°C to +125°C
• Additional features:
– Overload power limit
– Output short-circuit protection

2 Applications
• Low-power SAR and ΔΣ ADC driver
• ADC reference buffer
• Low-side current sensing
• Photodiode TIA interface
• Inductive sensing
• Battery-powered instrumentation
• Gain and active filter stages

3 Description
The OPAx863A devices are low-power, unity-gain
stable, rail-to-rail input and output, voltage-feedback
operational amplifiers, trimmed in package to offer
high precision performance with maximum input offset
voltage of 95-μV and offset drift of 1.2-μV/℃ for high
accuracy measurements over temperature.
Consuming only 800-μA per channel, the OPAx863A
devices offer a gain-bandwidth product of 50-MHz,
slew rate of 100-V/μs with a voltage noise density
of 6.3-nV/√Hz. The rail-to-rail input stage with 2.7-
V supply operation is useful in portable battery
powered applications. The rail-to-rail input stage
is well matched for gain-bandwidth product and
noise across the full input common-mode voltage
range, enabling superior performance with wide-input
dynamic range.
The OPAx863A devices include overload power
limiting to limit the increase in IQ with saturated
outputs, thereby preventing excessive power
dissipation in power conscious battery-operated
systems. The output stage is short-circuit protected,
making it conducive to ruggedized environments.