Power Supply Filter Calculations

Where we discuss new analog design ideas for Pro Audio and modern spins on vintage ones.
Post Reply
User avatar
mediatechnology
Posts: 3849
Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
Contact:

Power Supply Filter Calculations

Post by mediatechnology » Sun May 25, 2008 11:28 pm

We often get the question "how large of a filter cap do I need?"

Here's a way to calculate it:

Image

The load resistance term, Rl, can be estimated from the average voltage (at a hypothetical regulator input) divided by the maximum expected current. Fr is the ripple frequency. Using full-wave rectification Fr would be either 100 or 120 Hz. As a practical matter, use 100 Hz.

The full text where I obtained the equation is from Hemes:

https://www.ka-electronics.com/images/p ... _Temes.pdf

And the National Semiconductor Audio Handbook:

https://www.ka-electronics.com/images/p ... Design.pdf

Construction information for the Pico PSU board using the LM317/LM337 is here:

https://www.ka-electronics.com/PicoComp ... uments.htm
https://ka-electronics.com

VIDEO: "Antifa Viciously Attacks Little Girl [in Portland] Plus Leaked NY Times Documents Shock The World" https://www.infowars.com/watch/?video=5 ... 0017211639
Project Veritas: Google "Machine Learning Fairness" Whistleblower Goes Public, says: "burden lifted off of my soul." https://www.youtube.com/watch?v=g1VeElB ... e=youtu.be
If banned by YouTube: https://www.bitchute.com/video/g1VeElBAeas/

Post Reply