12volts @ 3 amps........any ideas?
I need this circuit to power my 12 inch lcd. It doesnt matter if the low voltage is 11-12 volts, as long as it can handle the 13.9 volts I get while my car is running. ANY help would be appreciated.
I figure that it wouldnt take much more than an 4 or 5 components, but this isnt my area.
If someone could draw a small diagram that would be great.
Eagerly awaiting someones help.
I personally think that the best way to do this would be to parallel 3 or 4 1amp low dropout voltage regulators... Why use 3 lower powered regulators when you can use a higher powered one??? I have tried this before (using one 5amp 12volt, low dropout regulator, and was unable to get a stable voltage even when the car was being revved.... Using regulators in parallel will mean a much more stable output with a lover voltage input.. 13volts should give you stable.. where as, with the 5amp IC, with over a 14volt input, the voltage was still low... (around 11volts i think) So, someone like to start an argument???
genesis use the LM1084-12 (National ) IC they are 12volt 5amps low dropout works like a charm in my setup ..... you will find a application design on their site ..
And james chill .......
Thanks Mastero, looks good.
Thats the IC I used.. :P the LM1084-12 and it wouldn't give me clean regulation without atleast a 14volt input.. try it if you want, might work, might not...
There is a 3A version of the LM7812 in a TO-3 style case. I have used it with success at about 2.5A. Note that you will need a nice sized heatsink. Sorry I don't know the exact part number.
Paralleling 3 1A regulators is a bad idea, as has been explained 300 times on this board already. It may work, it may not.
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It should work, but you will have excess heat produced as the regulators will "fight" with each other..
sometimes people just dont want the easy way out....!
aaron forget it .. dont argue
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