PSU Design - Electronic Circuits Projects Diagrams Free

yngndrw · 25th March 2008, 04:51 AM

Hi,

I'm interested in PSU design, well specific parts of it - Mainly the control / feedback.

As a project I'm looking at building a PIC-Controlled PSU. You set the Voltage / Current limits on a little LCD and it supplies this with a respectable accuracy. The PSU output would be based around PWM controlled directly by the PIC.

For this, what is the best way to work with the feedback. You would get the current Voltage / Current using the PIC's ADC, but then how would you use this information to manipulate the output - Especially since (In my experiance.) the PIC ADC's pickup quite a bit of noise.

Secondly (And slightly unrelated.), what are the best ways of reading a PIC's ADC to get an accurate value ? (In C using PIC 18F's, if it makes a difference.) Is it best to use an external ADC and if so, why ?

Thirdly, in a "normal" linear PSU with standard analogue components creating the feedback / control circuitry, what is the best way to combat voltage "droop" - I.e. The voltage drop that you get when you apply a large load.

Finally, again in a linear analogue PSU, what's the best way to control both voltage and current limiting while providing high accuracy, low droop and making the PSU "indestructable" ? (Able to withstand short-circuiting for an "infinate" period of time.)

In general I'm interested in design techniques and explanations, but example circuit diagrams are always helpful.

Thanks for any help.

ericgibbs · 25th March 2008, 07:38 AM

hi,

Your questions cover a wide range of topics for psu's.

There are some well written tutorials on the web, I Googled for 'psu design tutorial' and got lots of hits.

This looks a good starting point. It has links to most psu topics.

http://www.smps.us/smpsdesign.html

RAKS · 25th March 2008, 09:47 AM

Thank you.

yngndrw · 25th March 2008, 04:24 PM

Well the reason why I ask on here instead of just searching is for two reasons:
1) Google brings up a lot of information. Too much, really.
2) I was wondering if anyone on here had their own "tips and tricks".

Thanks for the link, I'll take a look now.

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25th March 2008, 04:51 AM	(permalink)
yngndrw	PSU Design Hi, I'm interested in PSU design, well specific parts of it - Mainly the control / feedback. As a project I'm looking at building a PIC-Controlled PSU. You set the Voltage / Current limits on a little LCD and it supplies this with a respectable accuracy. The PSU output would be based around PWM controlled directly by the PIC. For this, what is the best way to work with the feedback. You would get the current Voltage / Current using the PIC's ADC, but then how would you use this information to manipulate the output - Especially since (In my experiance.) the PIC ADC's pickup quite a bit of noise. Secondly (And slightly unrelated.), what are the best ways of reading a PIC's ADC to get an accurate value ? (In C using PIC 18F's, if it makes a difference.) Is it best to use an external ADC and if so, why ? Thirdly, in a "normal" linear PSU with standard analogue components creating the feedback / control circuitry, what is the best way to combat voltage "droop" - I.e. The voltage drop that you get when you apply a large load. Finally, again in a linear analogue PSU, what's the best way to control both voltage and current limiting while providing high accuracy, low droop and making the PSU "indestructable" ? (Able to withstand short-circuiting for an "infinate" period of time.) In general I'm interested in design techniques and explanations, but example circuit diagrams are always helpful. Thanks for any help.

25th March 2008, 07:38 AM	(permalink)
ericgibbs	hi, Your questions cover a wide range of topics for psu's. There are some well written tutorials on the web, I Googled for 'psu design tutorial' and got lots of hits. This looks a good starting point. It has links to most psu topics. http://www.smps.us/smpsdesign.html __________________ Eric "Good enough is Perfect" PIC tutorials: Gramo's: www.digital-diy.net/ Bill's: www.blueroomelectronics.com/

25th March 2008, 09:47 AM	(permalink)
RAKS	Thank you. __________________ Blatent advertising deleted! - moderator.

25th March 2008, 04:24 PM	(permalink)
yngndrw	Well the reason why I ask on here instead of just searching is for two reasons: 1) Google brings up a lot of information. Too much, really. 2) I was wondering if anyone on here had their own "tips and tricks". Thanks for the link, I'll take a look now.