So the other day I read through this article here.
https://www.dhtrob.com/overige/pdf/dhtrob_psu.pdf
I have been under the impression that using as big of a capacitor as possible in your filter stages along with large chokes is the way to go. Most of my PSUs involve an LCLCRC filter where I split the PSU into two rails off the first capacitor.
This article suggests that my approach might not be all that great because larger capacitors need more time to charge and lead to other issues. I have seen other articles that say something to the effect of "you should only use a large enough capacitor to get the job done".
I have seen some designs that use mondo 6000uf electrolytic PSU capacitors and I have seen some modern single ended designs that use capacitors in the range of 50uf or lower.
I just wanted to get your guys thoughts on the situation? Is more capacitance always a good thing? Or should you use a capacitor that achieves good dampening, has a critical frequency below 10hz and call it good, achieves the right amount of ripple reduction and call it good?
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Lastly I am very intrigued by this idea of using a low value capacitor and resistor at the last stage to filter out RF.
I tried to experiment with the idea inside of the PSU designer on a PSU I am working on and got wildly different results. In the image below I am getting a lot of hash. Is this right? Am I doing something wrong? Is this even a worth while rabbit hole to go down? What are your thoughts?
https://www.dhtrob.com/overige/pdf/dhtrob_psu.pdf
I have been under the impression that using as big of a capacitor as possible in your filter stages along with large chokes is the way to go. Most of my PSUs involve an LCLCRC filter where I split the PSU into two rails off the first capacitor.
This article suggests that my approach might not be all that great because larger capacitors need more time to charge and lead to other issues. I have seen other articles that say something to the effect of "you should only use a large enough capacitor to get the job done".
I have seen some designs that use mondo 6000uf electrolytic PSU capacitors and I have seen some modern single ended designs that use capacitors in the range of 50uf or lower.
I just wanted to get your guys thoughts on the situation? Is more capacitance always a good thing? Or should you use a capacitor that achieves good dampening, has a critical frequency below 10hz and call it good, achieves the right amount of ripple reduction and call it good?
------------------
Lastly I am very intrigued by this idea of using a low value capacitor and resistor at the last stage to filter out RF.
I tried to experiment with the idea inside of the PSU designer on a PSU I am working on and got wildly different results. In the image below I am getting a lot of hash. Is this right? Am I doing something wrong? Is this even a worth while rabbit hole to go down? What are your thoughts?
Apples and oranges...
Rob used CT transformer (DCR 710R), tube rectification, CLC filter.
You use single secondary, SS bridge, LC filter.
Rob used CT transformer (DCR 710R), tube rectification, CLC filter.
You use single secondary, SS bridge, LC filter.
Those changes will get rid of that initial peak, but it wont change the high frequency hash afterwards.
That hash only goes away if I enlarge the capacitor
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