Class D amp
Luka
If you want to use the supply for the amp you made reference to, I would follow the advice of Fredos and leave the supply unregulated and set the duty cycle to 50% for all the reason's that is discussed in that thread then you can use a protection circuit to shutdown the supply thru the shutdown pin of the SG3525 if there is an unbalance in either rail. I don't agree with the toroid core but it is used in the same type amps for cars and you are right about the chasis size very small.
chas1
Luka
If you want to use the supply for the amp you made reference to, I would follow the advice of Fredos and leave the supply unregulated and set the duty cycle to 50% for all the reason's that is discussed in that thread then you can use a protection circuit to shutdown the supply thru the shutdown pin of the SG3525 if there is an unbalance in either rail. I don't agree with the toroid core but it is used in the same type amps for cars and you are right about the chasis size very small.
chas1
Hi
Usage of toroid all depends on how it will work, and if needed.
Thanks for posting pic of project, if you sand me originals I can post then on photobuchet, so anyone can see values of components if someone will try to make them.
I will have it unregulated so that I don't have problems, I'll just synchronize supply with amp.
Usage of toroid all depends on how it will work, and if needed.
Thanks for posting pic of project, if you sand me originals I can post then on photobuchet, so anyone can see values of components if someone will try to make them.
I will have it unregulated so that I don't have problems, I'll just synchronize supply with amp.
Schematics
Luka
Good job, but you should note SMPS does not work. It has problems and I guess this forum should be able to resolve the issues. A fun challenge.
chas1
Luka
Good job, but you should note SMPS does not work. It has problems and I guess this forum should be able to resolve the issues. A fun challenge.
chas1
Hi
If snubber worker with low input voltage, will it still work the same as before vith high input voltage?
If snubber worker with low input voltage, will it still work the same as before vith high input voltage?
snubber
Luka
Checkout Pressman pg 416, snubbers should be calculated for current thru switch device at operating parameters.
chas1
Luka
Checkout Pressman pg 416, snubbers should be calculated for current thru switch device at operating parameters.
chas1
Hi
With this cap for filter I did get 480W from toroid just now, with almost no sag of voltage, just about 5v
With this cap for filter I did get 480W from toroid just now, with almost no sag of voltage, just about 5v
Micheal Price report
Luka & N-Channel
Here is the Article that you were searching for, It is posted in the thread my ucd.
M. Price's report
Here is the URL:
http://web.mit.edu/pricem/www/smps/report.pdf
chas1
Luka & N-Channel
Here is the Article that you were searching for, It is posted in the thread my ucd.
M. Price's report
Here is the URL:
http://web.mit.edu/pricem/www/smps/report.pdf
chas1
Hi
Yes thats the one
Tkank you very much for finding it.
BTW: I went up to 630w yesterday. Power clearly won't be a problem. Funny thing happend to resistors, they are four 15w each and each one was dissipating 120w in water. They got that hot that bubbles were coming out of them 😀 Apart from load heat there was non whatsoever from other elements. Can't wait to use it with some normal/usefull voltages
Yes thats the one
Tkank you very much for finding it.BTW: I went up to 630w yesterday. Power clearly won't be a problem. Funny thing happend to resistors, they are four 15w each and each one was dissipating 120w in water. They got that hot that bubbles were coming out of them 😀 Apart from load heat there was non whatsoever from other elements. Can't wait to use it with some normal/usefull voltages
Here is the link if you want to see it
http://s123.photobucket.com/albums/o286/first2ner/?action=view¤t=c0a9ef92.flv
http://s123.photobucket.com/albums/o286/first2ner/?action=view¤t=c0a9ef92.flv
Luka,
I like your level shifting method for the high side driver in your SMPS. I think I would like to consider that method again. It appears both simple and effective.
I like your level shifting method for the high side driver in your SMPS. I think I would like to consider that method again. It appears both simple and effective.
Hi Electrone
It is simple and effective as you said and it works great with only small component count to make SG and IR work.
It is simple and effective as you said and it works great with only small component count to make SG and IR work.
Luka,
Is the schemo you posted yours or Mr. Prices? I'm confused. 😕 Do you both use this discrete method of level-shift for the high-side MOSFET? I wonder why Mr. Price's SMPS did not work?
Anyway, I like the cross-conduction defeat feature between the two outputs of the '3525 and the MOSFETs. If the insertion of additional deadtime (100 W) fails to ensure no cross-conduction, then this certainly will.
Steve
Is the schemo you posted yours or Mr. Prices? I'm confused. 😕 Do you both use this discrete method of level-shift for the high-side MOSFET? I wonder why Mr. Price's SMPS did not work?
Anyway, I like the cross-conduction defeat feature between the two outputs of the '3525 and the MOSFETs. If the insertion of additional deadtime (100 W) fails to ensure no cross-conduction, then this certainly will.Steve
Hi
The schema and everything else is from Mr. Prices. I don't use discrete method of level-shift since I don't need one because of IR
Te problem was that the upper fet didn't close enought making shorts. In his design I don't like how he drives high side.
The schema and everything else is from Mr. Prices. I don't use discrete method of level-shift since I don't need one because of IR
Te problem was that the upper fet didn't close enought making shorts. In his design I don't like how he drives high side.
luka said:
I use the IR IC chips and have really always done it that way. I have to go back on my impression of the discrete level shifter because after simulating it in various configurations, I have found shortcomings with it.