logo weho

Switching Power Supplies: An In-Depth Guide

Switching power supplies excel in size and efficiency, making them a popular choice for powering many electronics. As with any device, designing switching power supplies requires careful attention to noise reduction.

This guide will provide you with an in-depth look at switching power supplies, including how they work and their advantages. With these tips in mind, you will be able to use switching power supplies confidently in your projects!

Switching Power Supplies

What is a Switching Power Supply?


Switching power supplies are an integral part of modern electronic products. They provide stable and efficient conversion of AC to DC and frequency regulation that can accommodate a variety of applications such as DC to DC, DC to AC, and AC to DC conversions.

The switching power supplies employ precise switch technology in order to render highly effective operation compared to linear power supplies which tend to be much less efficient due to the transformer-based approach used by the latter.

A switching power supply is most commonly used in applications requiring a high-efficient electrical system. This type of power supply is characterized by its ability to convert energy from one form to another at rapid speed, thus making it more efficient than other types of power supplies.

How Do Switching Power Supplies Work?


Switching power supplies have become the preferred choice for applications ranging from aerospace to military grade. Unlike their linear counterparts, switching power supplies offer improved efficiency and reduce heat output. So how do they actually work?

Linear AC/DC power supplies were initially used to convert AC power from the utility grid into DC voltage in residential appliances or lighting.

Despite low noise, their large size means that they are typically relegated to industrial and medical applications where small size isn’t necessary. On the other hand, switching power supplies are smaller, and more efficient at handling high power loads, and thus gained greater popularity.

Switching power supplies use a switch to rapidly turn the direct current into alternating current, producing a clean DC output. This is accomplished by using a feedback loop that regulates the voltage on the output side.

The switch rapidly turns on and off, allowing a short burst of current to flow through the load, then rectified and filtered to create the desired DC voltage.

History Of Switch Mode Power Supplies (SMPS)

Difference between a switching power supply and an SMPS


Switching power supplies have been around since the 1950s, but patenting of this technology dates back to 1976. Switching Power Supplies (SPSs) are electronic circuitry that utilizes semiconductor switches for efficient conversion of electrical current from DC to AC.

SPSs provide improved efficiency compared to traditional linear power converters as they only draw power from the input voltage when actively converting energy.

Switching Mode Power Supplies (SMPS) provide a higher power density than traditional Switching Power Supplies (SPS) and are typically used in electronic devices such as cell phones, computers, and other large-power applications where small size is paramount.

The technology behind SMPS allows for energy transfer at high-frequency levels of operation to meet the increasing demand for portable electronics. The terms “switching power supply” and “switch-mode power supply” are now often used interchangeably.

The Components of a Switching Power Supply


There are several key components that make up a switching power supply, including the switch itself, the transformer, the rectifier, and the filter.

Let’s take a closer look at each of these components and how they work together:


The switch is typically a transistor that can turn on and off very quickly. By turning the switch on and off rapidly, the power supply is able to control the amount of current flowing to the load.


The transformer is used to step up or step down the voltage as needed. In a typical switching power supply, a high-frequency transformer is used to convert the input voltage to a higher or lower voltage needed to drive the load.


The rectifier is used to convert the AC voltage from the transformer to the DC voltage. This is typically accomplished using diodes.


The filter is used to remove any unwanted noise or ripple from the DC voltage. This is typically accomplished using capacitors.

Feedback Loop

The feedback loop is another critical component of a switching power supply. It is used to control the output voltage by monitoring the actual output voltage and adjusting the switch as needed to maintain the desired output voltage.

These are the basic components of a switching power supply. By understanding how each of these components works, you can better understand how switching power supplies work as a whole.

120W desktop power supplies

Where are switching power supplies used?


Switching Power Supply technology is widely used for a variety of applications, as it offers power conversion with both high efficiency and reliability.

Industries that often rely on switching power supplies include aerospace, audio/visual, communications, computers, industrial, security, and military. These devices are well-suited for the demands of these industries’ varied needs and requirements.


The aerospace industry requires power supplies that can operate in harsh environmental conditions and provide reliable power for critical systems such as avionics, communications, and navigation.


Switching power supplies are used in various audiovisual equipment such as amplifiers, mixers, and speakers. These power supplies provide high-quality, stable power to ensure optimal performance and prevent damage to the equipment.


The communication industry relies heavily on switching power supplies for a wide range of applications such as routers, switches, and modems. These power supplies help ensure a steady flow of power, which is essential for maintaining smooth communication networks.


Switching power supplies are commonly used in desktop computers, servers, and other computer hardware. These power supplies provide the stable and efficient power needed to keep the computer running smoothly.


Industrial applications use switching power supplies for a range of purposes such as powering motors, controlling machines, and providing backup power. These power supplies are designed to operate in harsh environments and withstand extreme temperatures.


Security systems rely on switching power supplies for providing power to cameras, access control systems, and other security equipment. These power supplies help ensure that the security system remains operational at all times.


The military uses switching power supplies in a range of applications such as radar systems, communication equipment, and weapon systems. These power supplies need to be rugged and reliable to withstand the harsh conditions of military operations.

Switching power supplies are used in a variety of industries due to their efficiency, reliability, and versatility. From aerospace to military applications, these power supplies are an essential component of many systems that require consistent and stable power.

What is a switching power supply adapter?


Power supplies are essentially converters. Typically, they convert one or more parameters from supplied power to the parameter type and level required by a load or connected circuit.

A power supply adapter allows for the utilization of a power supply whose output was not specifically designed for the utilized input.

Power supply designs may consist of the conversion circuitry only or may consist of conversion and adapter circuitry on the same board.



Switching power supplies are a reliable and efficient way to power electronics. They are available in a variety of voltages, currents, and power levels to meet the needs of different applications.

WEHO is a global supplier of professional power supplies for a variety of industries. Our products have obtained the highest safety standards, including UL, cUL, TUV, CE, CB, and FCC. Since 2007, WEHO has been providing customers with quality power supplies at competitive prices from its facility in China.

Our experienced team is available to answer any questions you may have about finding the right product for your project.

    Send us a message

    You will receive our reply within 24 hours after you send the inquiry to us