Hi,
I have a question that has forever been bugging me. I'm in need of a bench PSU and I thought I'd build my own with a LM350 and a 4A transformer. Of course not the most elegant or efficient solution, but it's something feasible...
But that got me thinking: How is it that if I want a small 3A output, I need a pretty large transformer, while if you look at a modern PC power supply, they manage to put out 50A+, in an enclosure roughly the same size as it would take me to achieve a lowly 3A.
A.) How does this work? I don't know much about PC PSUs (as you can tell), but I've heard mention of "forward transistors" and stuff like that. How do they get such huge outputs out of little transformers. In fact, a 12V transformer for a PC PSU is probably half the size of the transformer I would use to get a fraction of the power.
B.) Can we take any of these modern PC PSU designs and use them in say a DIY power supply like the one I am attempting? Now if I wanted more power, I could use a switching regulator like an LM2576 or something, but I would STILL need a hugeass transformer. What gives?
Not sure who would know about this, but it's always something I've been curious about and I've never figured out.
Thanks.
I have a question that has forever been bugging me. I'm in need of a bench PSU and I thought I'd build my own with a LM350 and a 4A transformer. Of course not the most elegant or efficient solution, but it's something feasible...
But that got me thinking: How is it that if I want a small 3A output, I need a pretty large transformer, while if you look at a modern PC power supply, they manage to put out 50A+, in an enclosure roughly the same size as it would take me to achieve a lowly 3A.
A.) How does this work? I don't know much about PC PSUs (as you can tell), but I've heard mention of "forward transistors" and stuff like that. How do they get such huge outputs out of little transformers. In fact, a 12V transformer for a PC PSU is probably half the size of the transformer I would use to get a fraction of the power.
B.) Can we take any of these modern PC PSU designs and use them in say a DIY power supply like the one I am attempting? Now if I wanted more power, I could use a switching regulator like an LM2576 or something, but I would STILL need a hugeass transformer. What gives?
Not sure who would know about this, but it's always something I've been curious about and I've never figured out.
Thanks.
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