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New Member

I'm using the LM7805 to get a steady 5V at the output when i used a 12V at its input. I connected it as shown on page 21 of the attached document but i don't know why those value capacitors were choosen.

What would happen if i change one of the capacitor values?...I don't have any spare to try it out and see for myself...How does this LM7805 work?


New Member
Where os tje attached document. They are smoothing capacitors to work with the 7805. Little changes won't be a problem.


Well-Known Member
Most Helpful Member
It is called an IDIOT diode. It prevents damage from an idiot who connects an input with the wrong polarity.
Sometimes a huge IDIOT diode is connected across the power input (in parallel) to blow the fuse when an idiot connects an input with the wrong polarity.


IT doesn't matter if it's in series with a regulator and the dropout voltage isn't a problem.
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