• GAIN is the gain of the current-sense amplifier.

• VSN is the negative output swing of the device as specified in the Specifications.

Table 9-1 shows an example of the different results obtained from using five different gain versions of the

INA296x-Q1. From the table data, the highest gain device allows a smaller current-shunt resistor and decreased

power dissipation in the element.

Table 9-1. RSENSE Selection and Power Dissipation(1)

PARAMETER

EQUATION

RESULTS AT VS = 5 V

A1, B1

DEVICES

A2, B2

DEVICES

A3, B3

DEVICES

A4, B4

DEVICES

A5, B5

DEVICES

G

Gain

10 V/V

20 V/V

50 V/V

100 V/V

200 V/V

VSENSE

Ideal differential input voltage

VSENSE = VOUT / G

500 mV

250 mV

100 mV

50 mV

25 mV

RSENSE

Current sense resistor value

RSENSE = VSENSE / IMAX

50 mΩ

25 mΩ

10 mΩ

5 mΩ

2.5 mΩ

PSENSE

Current-sense resistor power dissipation

RSENSE × IMAX2

5 W

2.5 W

1 W

0.5 W

0.25 W

(1)

Design example with 10 A full-scale current with maximum output voltage set to 5 V.

9.2 Typical Application

The INA296x-Q1 is a bidirectional, current-sense amplifier capable of measuring currents through a resistive

shunt with common-mode voltages from –5 V to +110 V.

9.2.1 Current Sensing in a Solenoid Application

22 V

INA

OUT

IN+

IN–

V

S

GND

REF2

REF1

5 V

50 m

Control

Figure 9-1. Solenoid Drive Application Circuit

9.2.1.1 Design Requirements

In this example application, the common-mode voltage ranges from 0 V to 22 V. The maximum sense current

is 1.25 A, and a 5-V supply is available for the INA296x-Q1. Following the design guidelines from RSENSE and

Device Gain Selection, a RSENSE of 50 mΩ and a gain of 20 V/V are selected to provide good output dynamic

range. Table 9-2 lists the design setup for this application.

Table 9-2. Design Parameters

DESIGN PARAMETERS

EXAMPLE VALUE

Power supply voltage

5 V

Common mode voltage range

0 V to 22 V

Maximum sense current

1.25 A

RSENSE resistor

50 mΩ

Gain option

20 V/V

INA296A-Q1, INA296B-Q1

SBOSA32A – FEBRUARY 2023 – REVISED AUGUST 2023

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