oh i'm sorry it was a mistake 😛 i meant to say 28v :S
the +-28v would be perfecto for the tda7294 that's all i think
unfortunately no, i still don't have a schematic but seeing this is my first approach to the smps world i was thinking of following this circuit:
An externally hosted image should be here but it was not working when we last tested it.
What do you think?
Looks OK but I don't know what R7, R8, R9, and R10 are there for.
Look at other transformer designs for the power level you are expecting to use and copy that.
On a toroid (or other types of cores) the dots at the end of the windings on the schematic show common phasing of the windings. In a toroid as you show in post #16 ( the one with three windings) the wires coming out of the centre of the core are in the same phase. This is important.
Look at other transformer designs for the power level you are expecting to use and copy that.
On a toroid (or other types of cores) the dots at the end of the windings on the schematic show common phasing of the windings. In a toroid as you show in post #16 ( the one with three windings) the wires coming out of the centre of the core are in the same phase. This is important.
As you are working in low voltages, start with cheap parts, breadboard and experiment!
however, Step-down SMPS transformer or torroid cores will not work at more than a few milliamps. You need special material for this.
however, Step-down SMPS transformer or torroid cores will not work at more than a few milliamps. You need special material for this.
I've stepped down 12V to 1.25V @ 45A...and I did not use synchronized rectification ( I should have...would have got more current) using two toroids about 1.5" OD.
Do not take offense at my statement that you need to learn some more about SMPS and what a toroid core is.
Happy learning.
🙂
Synchronous rectification is used where efficiency is required for low voltage/high current SMPS.
It is actually a MOSFET that is turned on to become a low resistance path during the time period that the regular rectifying diode is forward biased.
The advantage is that you do not have the half a volt (or more) drop but a 1 or 2 milliohm connection.
Some SMPS controllers have the drive built in. Mine did but I did not know about it then.
There are also stand alone drivers but I have not investigated them.
Synchronous rectification is also called Active rectification.
There is so much to learn about SMPS.
🙂
It is actually a MOSFET that is turned on to become a low resistance path during the time period that the regular rectifying diode is forward biased.
The advantage is that you do not have the half a volt (or more) drop but a 1 or 2 milliohm connection.
Some SMPS controllers have the drive built in. Mine did but I did not know about it then.
There are also stand alone drivers but I have not investigated them.
Synchronous rectification is also called Active rectification.
There is so much to learn about SMPS.
🙂
hey i got another transformer(broke the other), and i saw this post:
http://electronics-diy.com/100w-car-subwoofer-amplifier.php
doesn't it make sense?? if you put 12v on the 5v line of the transformer won't i get aprox. +-30v at the output of the 12v line?
and also this transformer has a common ground, how do i now which pin is 5v / 12v and which wire is the ground for what?
http://electronics-diy.com/100w-car-subwoofer-amplifier.php
doesn't it make sense?? if you put 12v on the 5v line of the transformer won't i get aprox. +-30v at the output of the 12v line?
and also this transformer has a common ground, how do i now which pin is 5v / 12v and which wire is the ground for what?
it might, i mean they provide all information, the only thing missing is information about the transformer.... the only advise to use an atx tramsformer and separate the common gounds, but it seems my atx transformer(the new one) only has one ground for all connected to the same point on the transformer don't know why... any ideas ?
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