Hello, i decided to make a cheap bench supply to test a wide of range of breadboard circuits as i envolve myself far into the depths of electronics. So i went and dismantled the ATX PSU from an old computer that i had lying around in my house, and as it is 200W, it can provide sufficient power for any breadboard circuit and even some other stuff that i plan to do.
It's not a very old PSU, but it has that -5v rail, so it may be a bit old.
I came here to ask a few questions, because i know that a lot of guys here already did this kind of thing( Did an ATX bench PSU).
1) I want to make a cheap variable power supply, so i decided to for the LM317 voltage regulator, as it is linear, it has some inherent voltage drop( datasheet says Vin must be at least 3v bigger than Vout). So if i connect to the 12v rail and try to vary it's voltage, i'll not get a lot.
So i am thinking, connecting between 12v and -12v it's possible ? Because i'll give a lot more headroom for varying.
Also LM350 it's a possiblity to extend current capability.
2) Also to know what voltage am in, i could use voltmeter, with those panels, but i don't have one lying around and to buy one from ebay it takes 2 months to reach my house. I thought of making one with comparators, the only problem is that the resolution is going to be small, isnt it ? Extending the number of comparators and leds could make this really expensive. Any alternative ?
3) I was taking a look at this thread: variable ATX power supply and i saw the guy trying to mod one of the transistors, really smart move, but i don't know if this is possible with mine. If i upload some pictures like the guy did, can someone locate that amazing schematic ? I don't know here to find!
Thanks in advance.
Also there is a thread of @Dodgydave : variable ATX psu that explains how to do this modding that i asked about, but the videos arent available. He stated 4.9v to 28v on the 12v rail and that's really awesome. And 2v to 10v on the 5v rail, if i could mod that, it would be perfect.
It's not a very old PSU, but it has that -5v rail, so it may be a bit old.
I came here to ask a few questions, because i know that a lot of guys here already did this kind of thing( Did an ATX bench PSU).
1) I want to make a cheap variable power supply, so i decided to for the LM317 voltage regulator, as it is linear, it has some inherent voltage drop( datasheet says Vin must be at least 3v bigger than Vout). So if i connect to the 12v rail and try to vary it's voltage, i'll not get a lot.
So i am thinking, connecting between 12v and -12v it's possible ? Because i'll give a lot more headroom for varying.
Also LM350 it's a possiblity to extend current capability.
2) Also to know what voltage am in, i could use voltmeter, with those panels, but i don't have one lying around and to buy one from ebay it takes 2 months to reach my house. I thought of making one with comparators, the only problem is that the resolution is going to be small, isnt it ? Extending the number of comparators and leds could make this really expensive. Any alternative ?
3) I was taking a look at this thread: variable ATX power supply and i saw the guy trying to mod one of the transistors, really smart move, but i don't know if this is possible with mine. If i upload some pictures like the guy did, can someone locate that amazing schematic ? I don't know here to find!
Thanks in advance.
Also there is a thread of @Dodgydave : variable ATX psu that explains how to do this modding that i asked about, but the videos arent available. He stated 4.9v to 28v on the 12v rail and that's really awesome. And 2v to 10v on the 5v rail, if i could mod that, it would be perfect.