What are the major reasons for using high frequency isolation in switching power supplies?

What are the major reasons for using high frequency isolation in switching power supplies?

High efficiency, low-power dissipation, and high-power density (because of their small size) are the main reasons for designers to use switching regulators instead of linear regulators, especially in high-current applications. Moreover, switching regulators are able to boost, buck, and invert voltages.

Why is my PSU making a static noise?

That PSU has a double forward topology and some higher end graphics cards will have transient loads during games or benchmarks that will cause the main transformer to make a buzzing noise. Darkbreeze said: Sounds like a problem with the fan bearing although it’s hard to say without actually being there to hear it.

How to reduce the noise of a power rail?

To lower the noise of a power rail to a load (R L), you can make an L-C low-pass filter. (Courtesy of Wikimedia) The problem with adding LC circuits is that they have a natural resonant frequency. Thus, it may make your supply unstable or produce unacceptable ringing after transient load changes.

What kind of noise does a power supply make?

Intrinsic noise from your power supply and on the power rails in your PCB comes in four forms: Random noise in the frequency domain. This noise appears as thermal noise (i.e., Johnson-Nyquist noise) throughout the frequency domain.

How is decoupling used to reduce power supply noise?

Bypassing is used to reduce the noise current on power supply lines. Decoupling is the isolation of two circuits on a common line. The decoupling network is usually a low pass filter and the isolation is rarely equal in both directions. Decoupling is used to prevent transmission of noise from one circuit to another.

How is white noise related to switching noise?

This white noise (i.e., spanning throughout the frequency spectrum) is Gaussian distributed (i.e., changes in the magnitude in time follow a Gaussian process). Switching noise. This appears at specific frequencies on the output from a switching regulator (buck-boost converter, flyback/forward converter, VRM, etc.).