This circuit is a small +5V power supply, which is useful when experimenting with digital electronics. Small inexpensive wall transformers with variable output voltage are available from any ...

There is little to be said about this circuit. All the work is done by the regulator. The 7809 can deliver up to 2 amps continuous output whilst maintaining a low noise and very well regulated supply.

The aim: Create a 3.3V source from a –5V supply. You can obtain a precise, positive-output voltage from a negative-voltage supply with a boost converter and a linear regulator. The input and output ...

Fig 1. This efficient pre-regulator for a dc power supply uses an optical feedback loop to minimize dissipation rather than the traditional optically isolated TRIAC drivers. Fig 2. The PSpice ...