7.4 Device Functional Modes

7.4.1 Unidirectional Operation

The INA293-Q1 measures the differential voltage developed by current flowing through a resistor, commonly

referred to as a current-sensing resistor or a current-shunt resistor. The INA293-Q1 operates in unidirectional

mode only, meaning it only senses current sourced from a power supply to a system load as shown in Figure

7-2.

IN+

IN±

OUT

-

+

Buffer

Current

Feedback

5 V

GND

RL

R1

R1

Bias

48-V

Supply

Load

Figure 7-2. Unidirectional Application

The linear range of the output stage is limited to how close the output voltage can approach ground under zero-

input conditions. The zero current output voltage of the INA293-Q1 is very small, with a maximum of GND + 20

mV. Make sure to apply a differential input voltage of (20 mV / Gain) or greater to keep the INA293-Q1 output in

the linear region of operation.

7.4.2 High Signal Throughput

With a bandwidth of 1.3 MHz at a gain of 20 V/V and a slew rate of 2.5 V/µs, the INA293-Q1 is specifically

designed for detecting and protecting applications from fast inrush currents. As shown in Table 7-2, the INA293-

Q1 responds in less than 2 µs for a system measuring a 75-A threshold on a 2-mΩ shunt.

Table 7-2. Response Time

PARAMETER

EQUATION

INA293-Q1

G

Gain

20 V/V

Maximum current

100 A

Threshold current

75 A

Current sense resistor value

2 mΩ

Output voltage at maximum current

4 V

Output voltage at threshold current

3 V

SR

Slew rate

2.5 V/µs

Output response time

< 2 µs

www.ti.com

INA293-Q1

SBOS870A – MAY 2019 – REVISED SEPTEMBER 2020

Copyright © 2020 Texas Instruments Incorporated

Submit Document Feedback

15

Product Folder Links: INA293-Q1