OPAx863A High-Precision, 105-MHz, Rail-to-Rail Input/Output Amplifiers

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 OPA863A and OPA2863A devices (OPAx863A)

are low-power, unity-gain stable, rail-to-rail input

and output, voltage-feedback operational amplifiers.

These devices are trimmed in package to offer high-

precision performance with a 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

offer a gain-bandwidth product of 50 MHz, slew rate of

100 V/µs, and 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 excellent

performance with wide-input dynamic range.

The OPAx863A 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 these devices

conducive to ruggedized environments.

Package Information(1)(2)

PART NUMBER

CHANNEL COUNT

PACKAGE

OPA863A

Single

DBV (SOT-23, 5)(3)

OPA2863A

Dual

DSN (USON, 10)

(1)

For all available packages, see the orderable addendum at

the end of the data sheet.

(2)

For related products, see the Device Comparison Table.

(3)

Preview information (not Production Data).

ADS7057

14-bit

2.5 MSPS

R

S

+

–

3.3 V

AVDD

OPAx863A

C

CB

C

FILT

REF1933

3.3-V

Reference

5V

R

F

R

G

Z

OUT

Sensor

3.3 V

R

S

OPAx863A as a Precision SAR ADC Input Driver

Input Offset Drift (

V/C)

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

0

4

8

12

16

20

Precision Performance With Low Input-Offset-

Voltage Drift

OPA863A, OPA2863A

SBOSA95C – MAY 2022 – REVISED AUGUST 2023

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. UNLESS OTHERWISE NOTED, this document contains PRODUCTION

DATA.