Input Stage Offset Voltage Drift (PV/qC)

0

5%

10%

15%

20%

25%

30%

-0.4

0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

+

±

+

±

+

±

10 k

24.7 k

10 k

10 k

10 k

24.7 k

Over-

Voltage

Protection

Over-

Voltage

Protection

RG

REF

+VS

OUT

-VS

-IN

+IN

RG

O

IN

IN

REF

V

G V

V

V

:

G

49.4 k

G

1

R

Product

Folder

Order

Now

Technical

Documents

Tools &

Software

Support &

Community

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.

INA821

SBOS893B – AUGUST 2018 – REVISED MAY 2019

INA821 35-µV Offset, 7-nV/

√Hz Noise, Low-Power, Precision Instrumentation Amplifier

1

1 Features

1

•

Low offset voltage: 10 µV (typ), 35 µV (max)

•

Gain drift: 5 ppm/°C (G = 1),

35 ppm/°C (G > 1) (max)

•

Noise: 7 nV/

√Hz

•

Bandwidth: 4.7 MHz (G = 1), 290 kHz (G = 100)

•

Stable with 1-nF capacitive loads

•

Inputs protected up to ±40 V

•

Common-mode rejection: 112 dB, G = 10 (min)

•

Power supply rejection: 114 dB, G = 1 (min)

•

Supply current: 650 µA (max)

•

Supply range:

–

Single-supply: 4.5 V to 36 V

–

Dual-supply: ±2.25 V to ±18 V

•

Specified temperature range: –40°C to +125°C

•

Packages: 8-pin SOIC and VSSOP

2 Applications

•

Battery test equipment

•

Flow transmitters

•

ECG amplifiers

•

Analog input modules

•

Circuit breakers

•

Industrial process control

•

Lab instrumentation

3 Description

The INA821 is a high-precision instrumentation

amplifier that offers low power consumption and

operates over a wide single-supply or dual-supply

range. A single external resistor sets any gain from 1

to 10,000. The device has high precision as a result

of super-beta input transistors, which provide low

input offset voltage, offset voltage drift, input bias

current,

and

input

voltage

and

current

noise.

Additional

circuitry

protects

the

inputs

against

overvoltage up to ±40 V.

The INA821 is optimized to provide a high common-

mode rejection ratio. At G = 1, the common-mode

rejection ratio exceeds 92 dB across the full input

common-mode range. The device is designed for low-

voltage operation from a 4.5-V single supply, and

dual supplies up to ±18 V.

The INA821 is available in an 8-pin SOIC and 8-pin

VSSOP package, and specified over the –40°C to

+125°C temperature range.

Device Information(1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

INA821

SOIC (8)

4.90 mm × 3.91 mm

VSSOP (8)(2)

3.00 mm × 3.00 mm

(1) For all available packages, see the package option addendum

at the end of the data sheet.

(2) VSSOP (DGK) package is preview.

INA821 Simplified Internal Schematic

Typical Distribution of Input Stage Offset Voltage

Drift