UM1737 Datasheet, PDF (1/14 Pages) STMicroelectronics – How to use the product evaluation board STEVAL-ISQ014V1

UM1737
User manual
How to use the product evaluation board STEVAL-ISQ014V1 for
low-side current sensing with the TSZ121 operational amplifier
Introduction
This document describes how to use the product evaluation board STEVAL-ISQ014V1 for
low-side current sensing with the TSZ121 operational amplifier (op amp).
Power management mechanisms are found in most electronic systems and power
protection is of vital importance for them. One useful method of protecting an application is
by sensing the current. The low-side current sensing method consists of placing a sense
resistor between the load and the ground of the circuit. The resulting voltage drop is
amplified using the TSZ121.
This user manual describes how to accurately measure the current in your application and
describes the advantages of the low-side current sensing method. In addition, it provides:
• the schematics of the STEVAL-ISQ014V1 evaluation board
• a method for selecting the most appropriate components for your application
• theoretical and practical results
Figure 1. STEVAL-ISQ014V1 product evaluation board
May 2014
DocID025983 Rev 1
1/14
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