Stabilized dual power supply circuit

describe

The circuit given here is a specification, providing dual supply power of +12V and -12V from an AC source. A power supply like this is a very important tool on an electronics hobbyist's workbench. Transformer T1 drops the AC supply voltage and diodes D1, D2, step rectification work, D3 and D4. Capacitors C1 and C2 work as filtering.C3, C4, C7and C8 are the decoupling capacitors. ICs 7812 and 7912 are used for voltage regulation purposes where the former is a positive 12V regulator and the later is a negative 12V regulator. 7812 outputs +12 V and 7912, will - 12V.

Circuit diagram and parts list

Precautions

Good quality printed circuit board assembled circuit.

Transformer T1 can be a 230V main; 15-0-15 V, 1A secondary step-down transformer.

Fuse F1 can be a 500mA fuse.

Capacitors C1, C2, C5 and C6 must be rated at least 50V.