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, as well as validating and testing their design

implementation to confirm system functionality.

9.1 Application Information

The OPAx620 devices are CMOS, rail-to-rail I/O, high-speed, voltage-feedback operational amplifiers designed

for current and voltage sensing, high-speed, and other applications.

The amplifiers feature a 100MHz gain bandwidth, and 190V/µs slew rate, are unity-gain stable, and operate as

1V/V voltage followers.

9.2 Typical Applications

9.2.1 Low-Side Current Sensing

The need to accurately and quickly detect the load current through a low-side shunt resistor is a critical

application in systems requiring over-current, feedback control loops, battery monitoring, and power-supply

monitoring. Load current is often measured using low-side current sensing, which is when the voltage is

measured across a shunt-resistor that is placed between the load and ground. One common way to discretely

implement low-side current monitoring is to use a current-sense amplifier in a difference configuration, as shown

in Figure 9-1.

This approach offers a simple and cost-effective way to measure current, with benefits like:

1. High accuracy with proper offset and drift control.

2. Easy ground-referenced measurement (no need for differential high-voltage handling).

3. Simplified PCB layout and signal processing.

4. Designed for fast fault detection, especially in power electronics and automotive systems.

R

1

R

Sense

R

1

R

2

R

2

GND

V

CC

PGND

Out

GND

+

–

V

CC

I

Sense

OPAx620

Figure 9-1. Low-side Current Sensing Circuit

9.2.1.1 Design Requirements

For this design example, use the parameters listed in Design Parameters as the input parameters.

Table 9-1. Design Parameters

PARAMETER

EXAMPLE VALUE

Supply voltage, VCC

3.3V

Input offset voltage across temperature

±1mV

ISense

100mA - 2A

OPA620, OPA2620

SLOSEG2A – APRIL 2026 – REVISED JUNE 2026

www.ti.com

18

Submit Document Feedback

Copyright © 2026 Texas Instruments Incorporated

Product Folder Links: OPA620 OPA2620