INA181

2.7 V to 5.5 V

ADC

Microcontroller

Bus Voltage

±0.2 V to +26 V

GND

VS

Load

IN±

IN+

OUT

REF

+

±

0.1 µF

Copyright © 2017, Texas Instruments Incorporated

21

INA181, INA2181, INA4181

www.ti.com

SBOS793B – APRIL 2017 – REVISED NOVEMBER 2017

Product Folder Links: INA181 INA2181 INA4181

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Copyright © 2017, Texas Instruments Incorporated

9 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

9.1 Application Information

The INAx181 amplify the voltage developed across a current-sensing resistor as current flows through the

resistor to the load or ground. The ability to drive the reference pin to adjust the functionality of the output signal

offers multiple configurations, as discussed in previous sections.

9.1.1 Basic Connections

Figure 42 shows the basic connections of the INA181. Connect the input pins (IN+ and IN–) as closely as

possible to the shunt resistor to minimize any resistance in series with the shunt resistor.

NOTE: To help eliminate ground offset errors between the device and the analog-to-digital converter (ADC), connect

the REF pin to the ADC reference input and then to ground.

Figure 42. Basic Connections for the INA181

A power-supply bypass capacitor of at least 0.1 µF is required for proper operation. Applications with noisy or

high-impedance power supplies may require additional decoupling capacitors to reject power-supply noise.

Connect bypass capacitors close to the device pins.