Making a power supply for car to run a cd-rom

[DrSpanky]

Any one know a way to make a power supply unit that will run off a car battery and give you 12 and 5 volts to run a cd-rom drive?


Also do u have an idea how i can make a psu to run an old computer in the car with out using a computer psu and inverter?

Cause if i used an inverter all it would do is

Make 240 volts from 12v then the psu would take it and make 12v 5v and all that to run the computer.


Note: im not aiming to run a powerful computer just something like and old p1 or p2 with an lcd screen.

any ideas?

 

[CrashOveride]

Well car battaries give you 12v and you should be able to make somthing that drops it down to 5v (resistor)...

As for running the computer I don't know (though I guess you might be able to make somthing that gives you all the voltages from the 12v on the battery- might be pretty hard though).

 

[DrSpanky]

i dont care how hard it is im getting bored and need something to do and im should be driveing after x-mas and my car dont have a cd player

 

[CrashOveride]

i dont care how hard it is im getting bored and need something to do and im should be driveing after x-mas and my car dont have a cd player

Lol... Well you could just get a CD to tape thingy... but anyways, I bet if you search the net a bit you can figure out how to drop the voltage down to get that part done.

 

[greenman100]

Yeah, you can do it.

You need to regulate all three rails, though. (12v, 5v, and 3.3v) because when a car's alternator is spinning, it charges at 14.4v, no good for your purposes.

Get three LM1084 regulators, pre-regulated at 3.3, 5, and 12v. These are very simple to hook up. Connect all the grounds together to at least a 6gauge wire, and all the Vinputs together, and ot at least a 6 gauge wire. The voutputs will be your +3.3V, +5V, and +12V sources, and properly cooled with at least small heatsinks (and put some spare AS3 to use) will give you about 8A per rail.


3.3*8A = 26.4W
5*8A = 40W
12*8A = 96W

= your very own 162w power supply, which should be enough for a P1/P2, HSF, fans, HD, CDROM, and integrated video.

I'm not sure if the P1/P2 motherboards pull vcore off the 3.3, 5, or 12, but to be safe, I'd put another regulator in parallel with the 3.3 and 5. Why not? They're only $0.75 each. That'd give you like 225w, which should be plenty. Good luck.



http://www.national.com/pf/LM/LM1084.html

 

[CrashOveride]

Yeah, you can do it.

You need to regulate all three rails, though. (12v, 5v, and 3.3v) because when a car's alternator is spinning, it charges at 14.4v, no good for your purposes.

Get three LM1084 regulators, pre-regulated at 3.3, 5, and 12v. These are very simple to hook up. Connect all the grounds together to at least a 6gauge wire, and all the Vinputs together, and ot at least a 6 gauge wire. The voutputs will be your +3.3V, +5V, and +12V sources, and properly cooled with at least small heatsinks (and put some spare AS3 to use) will give you about 8A per rail.


3.3*8A = 26.4W
5*8A = 40W
12*8A = 96W

= your very own 162w power supply, which should be enough for a P1/P2, HSF, fans, HD, CDROM, and integrated video.

I'm not sure if the P1/P2 motherboards pull vcore off the 3.3, 5, or 12, but to be safe, I'd put another regulator in parallel with the 3.3 and 5. Why not? They're only $0.75 each. That'd give you like 225w, which should be plenty. Good luck.



http://www.national.com/pf/LM/LM1084.html

Thats awsome... Don't motherboards need other voltages as well though? there are a lot more than 4 wire colors on the connector... ( I get 4 from: 3.3v, 5v, 12v and one ground)

 

[DrSpanky]

on my psu there are
3 orange
1 blue
7 black - im thinking there ground
1 green - i think thats something to do with turning it on
4 red
1 grey
1 white
1 purple
and 1 yellow

im guessing red is 5volts, yellow is 12 and i would assume orange is 3.3

 

[Supertrucker]

12 5 3.3 gnd -3.3(i think) -5 & -12 at least, the negative voltages would be hard to get out of the car system, easier to just use an inverter and psu

 

[greenman100]

....you don't need negative voltages anymore for most motherboards. Check with the individual motherboard company. A quick phone call should do it.