/diy/ - Do It Yourself

[Anonymous No.379843]

Hey /DIY/ I was making a power supply schematic, anything wrong with it so far?

[Anonymous No.379874]

Anyone?

[Anonymous No.379881]

The top part looks like a normal linear power supply but wtf's going on in the bottom half of the diagram?

How much current are you expecting to draw from this? How is the 317 heatsinked?

[Anonymous No.379889]

>>379881
Someone I know said something about voltage dividers and whatnot, but I'd say the single pole 12 throw switch is self explanatory, also that outlet is gonna be where my leads go, I soldered an aligator clip to each wire of a wall plug (Which is dangerous in the hands of an idiot.) the regulator is heatsinked trust me, and I think I lost myself on the USB part.

[SiX No.379891]

>>379889
Ummmm....what?

[Anonymous No.379892]

>>379891
JUST A MOOOMENT

[Anonymous No.379895]

[Anonymous No.379900]

>>379889
Did I word this stupidly?

[Anonymous No.379906]

>>379889
OK, so you're making a constant regulated voltage with the LM317, then using resistor dividers to get different voltages out depending on what you want at the time?

The circuit will work much better if you use the resistor dividers to adjust the "ref" pin of the LM317 (pic related is the first schematic I found of the kind of thing I mean, but also check the LM317's data sheet). The circuit you have will result in very "soft" regulation, it will droop a lot under load, you're not really using the 317's ability to regulate.

[Anonymous No.379907]

>>379900
made as much sense as the bottom part of the schematic... none

What EXACTLY are you trying to do?

[Anonymous No.379919]

>>379906
Ah, yes thank you.