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DC gain of SMPS transfer function?

eem2am

Aug 3, 2009
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Hello,
The following equation (2A-22) , on page 232 of Basso's book (switch mode power supplies) is the small signal power stage transfer function for a buckboost converter, in current mode, CCM.

Please advise on what is the DC gain of this transfer function?

I am actually using it for a flyback (flyback is derivative of the buckboost) and my Ns/Np for the flyback is 0.837.

Pages 225, 226 explain what the parameters are
Pages 234, 235, explain how to convert equation 2A-22 for a flyback
Page 233 also shown as it shows the poles and zeros
 

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davenn

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Sep 5, 2009
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its his other nick on that forum


Dave
 

eem2am

Aug 3, 2009
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it might be my colleague trying to get one-up on me.

Basically DC gain will be gotten by putting w=0.
But there are adjustements to vout and R(LOAD)...due to the trafo.
Does vout become vout*np/ns?, the book doesn't make this clear
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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This is strange, Someone called Flyback has exactly the same post as you on another forum.

Check to see if they've also posted about optocouplers recently...

edit: yeah, that's him. Looks like he spends his time getting caned there and then posting here expecting a different response (and not getting one)
 
Last edited:

davenn

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hey John

he loves spreading his garbage LOL

Dave
 

jpanhalt

Nov 12, 2013
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Frankly, I thought that choice of nick's was ironic. A little glyphosate judiciously applied might help.

John
 
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