PWM IC | Pulse Width Modulation

PWM IC | Pulse Width Modulation​

There are some components on the motherboard of a laptop that use the technology PWM (Pulse Width Modulation) or Pulse Width Modulation to regulate that is decreases the board voltages.

They are known as PWM IC. The letter U is used to represent it on the motherboard.


Like every Integrated Circuit, the PWM IC has a more complex operation because it relies on receiving pulses and exchanging information in conjunction with other components through their terminals.


The main function of PWM IC is to generate the famous Switching Sources, which will be responsible for supplying all motherboard circuits.

The following image shows the example of a PWM IC model TPS51125.

In this image below you can see in the center a PWM IC pointed by an arrow.

This component may have different amounts of terminals depending on the model.

Use scrap motherboards to learn how to remove and place this component. Motherboard Removal Technique: Hot Air Station and solid flow to aid removal.

How to test PWM IC:​

Because it is an IC (Integrated Circuit), the test of this component is done by measuring some of its terminals, we should be use schematic or datasheet to know the input pin and output pin.