madbeanpedals::forum

Projects => General Questions => Topic started by: skypn on October 16, 2021, 06:06:28 PM

Title: Power Supply Question
Post by: skypn on October 16, 2021, 06:06:28 PM
Consider this schematic:
(https://i.ibb.co/gvdJ778/Power-Supply.jpg) (https://ibb.co/mv04BBK)
I have seen the same PS, but only R1 is placed after D1. Is there a difference?
TIA
Title: Re: Power Supply Question
Post by: skypn on October 16, 2021, 06:14:52 PM
And also, what type should C2 be? MLCC, or film?
Title: Re: Power Supply Question
Post by: Zerro on October 16, 2021, 07:10:34 PM
Order of R and D is not important. 100nF capacitors in power supplies are better ceramic, here for minimally 12V but better for 25V.
Title: Re: Power Supply Question
Post by: jimilee on October 16, 2021, 10:41:45 PM
Quote from: Zerro on October 16, 2021, 07:10:34 PM
Order of R and D is not important. 100nF capacitors in power supplies are better ceramic, here for minimally 12V but better for 25V.

Ceramic, not metal film or even mlcc? Don't see to many people using ceramic values above 1000pf. For pedals anyway.
Title: Re: Power Supply Question
Post by: jimilee on October 16, 2021, 10:43:53 PM
Quote from: skypn on October 16, 2021, 06:06:28 PM
Consider this schematic:
(https://i.ibb.co/gvdJ778/Power-Supply.jpg) (https://ibb.co/mv04BBK)
I have seen the same PS, but only R1 is placed after D1. Is there a difference?
TIA

While the order doesn't matter, I'm not sure why anything would be placed before the protection diode. Just a preference, I suppose. I will typically use metal film in the power section.
Title: Re: Power Supply Question
Post by: Zerro on October 16, 2021, 11:02:05 PM
I use ceramic multilayer. The lowest ESR and ESL, tiny size, high current peak. Not so depending at temperatures. Class1 as so class2. It worths to invest to it.