Many designs that make use of transistors and integrated circuits are powered by a 6 Vvoltage source, usually provided by small, medium or large cells or batteries. However, batteries are expensive and exhaust quickly in many cases.
If it is possible to feed these circuits on the bench by a fixed source, the economy is clear. The circuit we give next does just that, replacing 4 small, medium or large cells, that is, providing a current of up to 1 amp.
Simple to assemble, it is an economical solution ideal for those who do many experiments and electronic assemblies. With it, the use of batteries can be limited only to portable applications.
In figure 1 we have the complete diagram of the power supply.
The arrangement of the components on a terminal strip is shown in figure 2.
Note that we use the 7805 5 V integrated circuit. If the reader finds the 7806 and wants to use it, simply remove the two diodes from the adjustment terminal by connecting it directly to earth. To increase the output of the 7805 by just over 1 V, we use just two diodes, D3 and D4.
The transformer has primary winding according to the local and secondary grid of 7.5 + 7.5 V or even 9 + 9 V, and current of 1 A. If the reader has a lower current transformer, eg 500 mA, can use, but its source will provide a maximum current of 500 mA.
The diodes are equivalent and the capacitor C1 must have a working voltage of at least 16 V. The integrated circuit must be mounted on a heat radiator. At the source output we use terminals where the input wires of the supplied device will be trapped. Wires with claws of different colors may also be used to identify the positive and negative.
To experiment, just plug a multimeter into the output and check the voltage, or a 6 V lamp.
Material list
CI-1 - 7805 - integrated circuit, voltage regulator
D1 to D4 - 1N4002 - silicon diodes
C1 - 1000 uF x 16 V - electrolytic capacitor
C2 - 100 uF x 12 V - electrolytic capacitor
S1 – On/Off switch
F1 - 500 mA - fuse
More:
Terminal bridge, power cable, fuse holder, posts, alligator clips, mounting box, wires, solder, etc.
