Linear vs Switching DC Power Supplies - What's the Difference?

Hello and welcome to another Kikusui Electronics Youtube video. Today I'm going to discuss the two major types of DC power supply and the pros and cons of each. There are two main designs for DC power supplies: linear DC power supplies and switching DC power supplies. To represent each type I have the PWR-01 switching power supply and the PMX-A linear DC power supply. Although both of these instruments are designed to supply DC power to electrical and electronic circuits, the way in which the power is provided is completely different. Linear power supplies like the PMX-A utilize a transformer to drop voltage from the AC line to a much lower AC voltage then use a series of rectifier circuitry and filtering processes to produce a very clean DC voltage. On the other hand, switching DC power supplies regulate output voltage through a process known as pulse width modulation. This process generates some high frequency noise but enables the power supplies to be highly power efficient with a small form factor. The first thing you will notice when comparing these two models is the size difference. Despite having a wider power range than a linear power source of the same power, the PWR-01 switching power supply has a much smaller form factor than the linear PMX-A, because it does not require a bulky transformer to produce DC voltage. When it comes to efficiency, the switching DC power supply has a clear advantage over the linear type. The extremely high efficiency as well as compact size makes switching DC power supplies the more flexible and broadly used option between the two power supply types. However, there are other clear advantages when using a linear power supply like the PMX-A. In addition to increased reliability, a linear power supply is virtually immune to noise and electromagnetic interference, making it perfect for sensitive DUTs like medical equipment and low-noise amplifiers. Linear power supplies also have vastly superior transient response, meaning that much less time is required for the output voltage to recover from changes in the load. In conclusion, both switching and linear DC power supplies have their respective advantages and disadvantages, which will all depend on the requirements of the test engineer using the instrument. Switching power supplies offer extremely high efficiency and flexibility in a compact chassis, but are far more susceptible to electronic noise when compared with their linear counterparts. Linear power supplies are bulkier and less efficient than switching power supplies, but offer unparalleled noise and response speed performance. And that's all for today's video, for any questions regarding DC power supplies or any other electronic test and measurement instruments, please click on the link below or contact us at our overseas email. Thank you for watching.

Channel: Kikusui Electronics Channel

Views: 84,788

Keywords: power, supply, power supply, programmable, linear, switching, DC, test equipment, kikusui, T&M, chroma, keysight, ametek, portable

Id: v_HtdbsV69k

Length: 3min 9sec (189 seconds)

Published: Mon May 20 2019