INA241x –4-V to 110-V, Bidirectional, Ultra-Precise Current Sense Amplifier With

Enhanced PWM Rejection

1 Features

• Enhanced PWM rejection optimized for systems

subject to switching common-mode voltages

– Supports switching frequencies up to 125 kHz

• Wide common-mode voltage:

– Operational voltage: −4 V to +110 V

– Survival voltage: −20 V to +120 V

• Bidirectional operation

• High small signal bandwidth: 1 MHz (at all gains)

• Slew rate: 5 V/µs

• Step response settling time to 1%: 1 µs

• Excellent CMRR

– 160-dB DC-CMRR

– 93-dB AC-CMRR at 50 kHz

• Accuracy:

– Gain error (maximum)

• Version A: 0.05%, 2.5 ppm/°C drift

• Version B: 0.1%, 5 ppm/°C

– Offset voltage (maximum)

• Version A: ±12 µV, ±0.25 µV/°C drift

• Version B: ±150 µV, ±0.5 µV/°C drift

• Available gains:

– INA241A1, INA241B1 : 10 V/V

– INA241A2, INA241B2 : 20 V/V

– INA241A3, INA241B3 : 50 V/V

– INA241A4, INA241B4 : 100 V/V

– INA241A5, INA241B5 : 200 V/V

• Package options: SOT23-8, VSSOP-8

2 Applications

• Motor drives

• Solenoids and actuators

• Injection molding machine

• Cordless power tools

• Medical cordless tools

• Drone propeller speed control

3 Description

The INA241x is an ultra-precise, bidirectional current

sense amplifier than can measure voltage drops

across shunt resistors over a wide common-mode

range from –4 V to 110 V, independent of the supply

voltage. The high-precision current measurement

is achieved through a combination of low offset

voltage (12 µV, maximum), small gain error (0.05%,

maximum) and a high DC CMRR (typical 160 dB, 10

bidirectional measurements in switching systems that

see large common-mode transient voltage levels at

the device's inputs. The enhanced PWM rejection

circuitry inside the INA241x ensures minimal signal

disturbance at the output due to the common-mode

voltage transitions at the input.

The INA241x operates from a single 2.7-V to 20-V

supply, drawing 3 mA of supply current. The INA241x

is available in five gain options: 10 V/V, 20 V/V, 50

V/V, 100 V/V, and 200 V/V. Multiple gain options

allow for optimization between available shunt resistor

values and wide output dynamic range requirements.

The INA241x is specified over operating temperature

range of −40°C to +125°C and is offered in a space-

saving 8-pin SOT-23 and 8-pin VSSOP package.

Device Information(1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

INA241A

INA241B

SOT-23 (8)

2.90 mm × 1.60 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)

Package is preview only

+

Supply

(2.7 V to 20 V)

IN+

IN±

REF2

REF1

OUT

Typical Application - Inline Motor Control

INA241A, INA241B

SBOSA30 – 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.