LM317 1-25 Volts Variable DC 1.5 Amp Power Supply

An cheap and easy-to-understand circuit that leverages the LM317 DC voltage regulator IC to create a variable voltage DC power supply with up to 1.5 Amps of current. This power supply is likely to find numerous uses on your bench or in your workshop.

The LM 317 is a versatile integrated circuit that has thermal and over-current protection, so the DC output does not really need an fuses for protection, since the device will automatically shut off if it becomes too hot. The LM317 specifications allow the device to go up to 37 VDC, however this circuit only goes up to 25 Volts.

The AC transformer must always be at least few volts higher than the maximum output voltage you will want from this circuit. Also, remember that the transformer should be capable of providing the current that you'll require, up to the 1.5 amps, as per the LM317 specifications.