electronic-lab
Done

Split-Rail Linear Power Supply ±15 V

· #power supply #linear power supply #7815 #7915

Contents

A simple split-rail linear power supply for experiments with low-power amplifiers and audio signals. The project is easy to build and does not take much time, and a supply like this is good to have in the workshop.

The power supply on a stripboard inside its box, next to the empty half of the box

Mains voltage

This project works with mains voltage, so you have to be very careful. If you build it yourself, you do so at your own risk.

Schematic

Schematic of the ±15 V split-rail power supply

The schematic shows that very few parts are needed:

  • fuse and fuse holder,
  • 230 V / 2 × 18 V centre-tapped transformer,
  • bridge rectifier,
  • six capacitors,
  • voltage regulators, positive (L7815) and negative (L7915),
  • project box,
  • prototyping board.

Building it

First, cut the prototyping board to size so that it fits in the box. Then place the components, solder them to the board and make the connections with solid core wire.

For the outputs, I recommend 4 mm banana sockets in three colours, for example black for ground, red for +15 V and blue for −15 V.