Sometimes, to develop some applications with TTL technology that is quite common or in applications with microcontrollers, we need a power supply that provides us with 5 Volts constant.


On the other hand, the university practices in the subject of the digital electronics lab requires many hours of design and assembly, this project comes in handy to do such practices in the hours when the labs are closed.

Figure 1: Image of the power supply mini.


The circuit is based on a voltage regulator (the 7805) whose input is 9 volts and outputs as stable 5 volts. With a few more components, a diode has been included to exert an on-light indicator, a capacitor so that the voltage at the output does not change abruptly, a switch to switch the source on and off, and a protective diode When we put the battery upside down, the circuit will not break. The scheme is as follows:

Figure 2: Diagram of the power supply unit.


Once all is set, the power supply is as follows in the following images:


Figure 3: Top view of the power supply mini.


Figure 4: Bottom view of the power supply mini.


Next, I must give you an image of the mini-duct in operation, connected to an ultra-violet led used in the solar-powered UV lamp.


Figure 5: Image of the minifuente in operation.