INA851 Precision, Low-Noise, Fully Differential Output Instrumentation Amplifier

With Optional Attenuating Gain

1 Features

• Gain programmable from

G = 0.2 to 10,000 by using external resistor

• Fully differential outputs with integrated clamping

• Input overvoltage protection to ±40 V beyond

supplies at G = 1

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

• Low offset drift: 0.1 µV/°C (typ), 0.4 µV/°C (max)

• Low input bias current: 5 nA (typ)

• Input stage noise: 3.2 nV/√Hz, 0.8 pA/√Hz

• Wide bandwidth: 22 MHz at G = 0.2,

15 MHz at G = 1

• Common-mode rejection: 106 dB (min) at G = 10,

120 dB (min) at 100 ≤ G ≤ 1000

• Power supply rejection: 110 dB (min) at G = 1

• Supply current: 6 mA (typ)

• Supply range:

– Single supply: 8 V to 36 V

– Dual supply: ±4 V to ±18 V

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

• Tiny package: 16-pin RGT

2 Applications

• Analog input module

• Flow transmitter

• LCD test

• Electrocardiogram (ECG)

• Surgical equipment

• Oscilloscope (DSO)

• Weigh scale

• Semiconductor test

3 Description

The INA851 is the industry's first high-precision

instrumentation amplifier with fully differential outputs.

This device is optimized to drive inputs of modern

high performance analog-to-digital converters (ADCs)

with fully differential inputs. The INA851 operates over

a very-wide, single-supply or dual-supply range. The

output stage gain may be set to either 0.2 or to 1 by

shorting or floating two pins. A single external resistor

sets any input stage gain from 1 to 10,000.

Compared to other amplifiers in the same class,

the INA851 offers very-low input bias current and

low input-referred current noise as a result of super-

beta input transistors. A state-of-the-art manufacturing

process provides exceptionally low voltage noise,

input offset voltage, and offset voltage drift. The

device outputs feature built-in clamping circuitry to

protect the ADC or downstream device against

overdrive damage.

The device is designed for operation from an 8-V

minimum single supply, as well as with dual supplies

up to ±18 V.

Device Information

PART NUMBER

PACKAGE(1)

BODY SIZE (NOM)

INA851

VQFN (16)

3.00 mm × 3.00 mm

(1)

For all available packages, see the package option

addendum at the end of the data sheet.

+

–

RG

VS+

OUT+

VS

IN

IN+

RG+

OUT

VOCM

G02

(1)

G02+

(1)

3 k

5 k

5 k

3 k

5 k

1.25 k

5 k

1.25 k

LDO

LDO

VCLAMP+

VCLAMP

ADC

INP

INN

FDA_IN

FDA_IN+

+

–

–

+

INA851

15 V

15 V

5 V

4

3

2

1

16

15

14

13

7

5

6

9

10

11

12

Overvoltage

Protection

Overvoltage

Protection

+

–

(1) Short OUT to G02 and OUT+ to G02+

for output stage G = 0.2 option.

VDD

VSS

INA851 Simplified Application

INA851

SBOS999 – MARCH 2022

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. ADVANCE INFORMATION for preproduction products; subject to change

without notice.