Simple Programmable Power Supply using LM317 Circuit Diagram

Build a Simple Programmable Power Supply using LM317 Circuit Diagram. This is the Programmable Power Supply using LM317 Circuit Diagram type of the circuit simple and useful, it is a programmable DC power supply using LM317. This circuit can set the output voltage for transistors.

 The operation is simple, the transistors (T1-T4 = 2N2222 or any NPN transistors) are connected to resistors R which will grounded to determine the output voltage when one of the points ABC and D receives voltage, it makes the T corresponding drive your R to ground, so the voltage Vout changes according to the R, as you can see in the table below. The maximum voltage of this circuit is 27V when the input voltage is 28V.

 Programmable Power Supply using LM317 Circuit Diagram

This is when the output voltage of the DA is connected to Vin. (Values ​​of the resistors R)

R	Vout
100	1.8
330	3.0
470	4.0
1K	7.3
2.2K	13,5
3.3K	18,0