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Old 07-07-2021, 06:30 PM   #134
Join Date: Apr 2021
City & State: Islamabad
My Country: Pakistan
Line Voltage: 220VAC 50Hz
I'm a: Knowledge Seeker
Posts: 12
Red face Re: Dell 2007FPB teardown

Originally Posted by Behemot View Post
That's correct, ~230 V AC times square root of 2 equals to a bout 325 V. Where would DC appear from on the transformer? Since when can transformer transform direct current? A switch (usually transistor) cuts the DC into some kind of AC wave which can only than be transformed to higher or lower voltage.

The key value here is frequency. Low-frequency transformers (like the networks 50- or 60Hz) are huge and infficient for higher power passing through them. Switched-mode power supplies work usually within the 60-100 kHz range (but generaly can operate anywhere between 10 kHz and 10 MHz).
OH!! WHAT Was I Thinking... Sorry you are right ! about That AC Coming or going to Transformer, Transformer would never work on DC either for Primary or Secondary as it works with the Inductance Phenomenon.

Still, I need the Codes for the resistors, and Zener Diodes, Furthermore if you find out any Problem with the PCB, Solder Joints, or shorts, any help would be Greatly Appreciated !

And one thing more that's been messing up my mind, I asked that in my Previous post as well, why convert it into DC if we want to step down it later , why not step down AC Directly and then Convert it into dc?

Last edited by knightace; 07-07-2021 at 06:32 PM..
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