It couldn’t be simpler but you have to admit that a small adjustable portable power supply like this one will be really handy. The main part of the PSU is an LM317 linear voltage regulator which ...

This design idea revisits another: “PWM power DAC incorporates an LM317.” Like the earlier circuit, this one implements a power DAC by integrating an LM317 positive regulator into a mostly passive PWM ...

A driver is built using the LM317 variable regulator, resistor, power supply, and the GPU heat sink to keep things cool. Check out the video after the break to see the laser cutting tape ...