12V push pull SMPS

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Hi

are 5x0.5 mm diameter wires not enough for about 30A current (max power)???
Depends on what you want to do, if you want to burn them...
Ok if I say it differently, no it is not, You will have to use 10x0.5mm or better yet 10x 0.8mm or more wires.

I used I think it was 12x0.5mm for each primary, loaded supply with ~320w and wires heated up so much inside 30s that I could have fingers on it, and primary current was only about 25A...So you see what I mean by you will burn them... Ok my test was 320w continuous, not music or something, but still, use more wire
 
The IRF3205 are awesome for a TO-220 pkg!!!
Would be great replacements for any bad SMPS or inverters
110A 200W is insane for a TO-220 Thanks for the info on these!!!


Now the NTY100N10 have better thermal performance due to the larger package, and higher dissipation (313W) so for projects that get the MOSFETS hot, or switch at higher voltage, these are well suited.

Besides 12V SMPS projects, have any of you folks made power inverters or UPS supplies???
 
Well i intend to use the supply for audio amp 2x80W max. I'll do some tests after I finish the smps to see how much the primary will heat up because I don't want to dismantle the transformer since I spent a lot of time to wind it. If it gets too hot I will rewind it because I don't like very much the idea of burning it.
;)
 
kozetot said:
Well i intend to use the supply for audio amp 2x80W max. I'll do some tests after I finish the smps to see how much the primary will heat up because I don't want to dismantle the transformer since I spent a lot of time to wind it. If it gets too hot I will rewind it because I don't like very much the idea of burning it.
;)

For that low of power it may work OK, but if it gets hot, why not wind as much as you can in parallel to handle more power...
 
Hi,
If it goes hot I will certainly do so.
here is a pic of the transformer
 

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Now the NTY100N10 have better thermal performance due to the larger package, and higher dissipation (313W) so for projects that get the MOSFETS hot, or switch at higher voltage, these are well suited.

Much better to go with larger number of MOSFET`s with small, or even witout heatsinks, than stick with a pair devices that dissipating hungreds of watts. In addition TO220 better than TO247 or TO264 at high switching speeds due to less inductance as was specifed above by Eva, and devices in large packages are cost a lot of money.
 
EWorkshop1708 said:
.......Now the NTY100N10 have better thermal performance due to the larger package, and higher dissipation (313W) so for projects that get the MOSFETS hot, or switch at higher voltage, these are well suited......

Per EVA's caution, I would stay away from the '100N10's for high-frequency stuff (like SMPS), unless your PWM controller has a really stout output section. Else, I would use a dedicated driver chip, or an NPN-PNP buffer capable of handling sufficient current at sufficient speed.

Kozetot: Nice Toroids.
 
Tolik said:


Much better to go with larger number of MOSFET`s with small, or even witout heatsinks, than stick with a pair devices that dissipating hungreds of watts. In addition TO220 better than TO247 or TO264 at high switching speeds due to less inductance as was specifed above by Eva, and devices in large packages are cost a lot of money.

true. when I was planning on my big SMPS, I looked for IRFP064 as main switching devices. didn't find any but found a lower current variant IRFP054. the cost was 4X IRFZ44. so I used many IRFZ44 instead.:smash:
 
N-Channel said:


Per EVA's caution, I would stay away from the '100N10's for high-frequency stuff (like SMPS), unless your PWM controller has a really stout output section. Else, I would use a dedicated driver chip, or an NPN-PNP buffer capable of handling sufficient current at sufficient speed.

I've never liked the idea of directly driving the MOSFETS with the PWM IC being I've saw so many blown car amps with that setup.

Was thinking 2 or 3, or even 5 pairs :eek: of the 100N10s (just got 10 samples from OnSemi :D ) and driving them with MJE15034/35 transistors driven by a TL494 PWM IC. Should be stout enough I imagine. Also Have 10 TO-220 NTP75N06's to play with.
I'll experiment and see.

Although I'd like to get a bunch of IRF3205.......
 
EWorkshop1708 said:


I've never liked the idea of directly driving the MOSFETS with the PWM IC being I've saw so many blown car amps with that setup.

Was thinking 2 or 3, or even 5 pairs :eek: of the 100N10s (just got 10 samples from OnSemi :D ) and driving them with MJE15034/35 transistors driven by a TL494 PWM IC. Should be stout enough I imagine. Also Have 10 TO-220 NTP75N06's to play with.
I'll experiment and see.

Although I'd like to get a bunch of IRF3205.......

Try the IRFB4110 100V 180A!!! 370W 3.5mohm in TO220 package.
The gate charge is quite huge, 150nC per device. I use it in pairs
to drive a push-pull transformer of around 1kW.
To drive these mosfets I think that the better solution is to use a dedicated low side mosfet driver IC between the controller IC (eq. the SG3525) and the mosfets gates. The better I have ever used is the Texas Intruments UC37322 rated for 9A of pulsed current.
 
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