how to build dc power supply with +12v 0 -12v

[qqinternet]

hi there,

i want to run op amp so b4 that i need a dc power supply running +12v 0 -12v can anyone help me tq.

liew

 

[errakeshpillai]

hi there,

i want to run op amp so b4 that i need a dc power supply running +12v 0 -12v can anyone help me tq.

liew

You can use a voltage regulator IC:- LM 7812
I think this circuit will help you.

 

[qqinternet]

thx for that .and u got any circuit for the situation that if i have an old fuctioning dc adapter which is 12v 1A rating can i make it to supply +12v 0 -12v ?

 

[errakeshpillai]

With one dc adapter I probably don't know any method to use it for a 12-0-12V supply.
But its possible with two dc adapters..

 

[ark5230]

Complicated methods may provide this but it will be convenient to adopt a design as shown.
If at all you need to simplify it at the cost of its utility and versatility, you can replace the bridge using half wave rectification. You can drop the two 1N4004 diodes. You can drop the LED's and their series resistors. Then it would look pretty simple.
The input supply (transformer with mid tap) preferably should be more than 15V (15-0-15). VR1 is 7812 and VR2 is 7812 as you need +12 0 -12 supply.