Power Supplies

Types of cells / batteries. Primary batteries (non-rechargeable): Dry, mercury, alkaline. Secondary batteries (rechargeable): Nickel-Cadmium Alkaline, Lead

Electric batteries, by means of a chemical reaction, produce the following: At its negative terminal, there are a lot of electrons (negatively charged), and at its positive terminal, there is a lack of electrons (negatively charged).

Voltage sources, whether batteries, generators, etc., are not ideal (perfect). A real voltage source is composed of an ideal voltage source in series with a resistance called internal resistance.

Many electronic circuits need a direct current (DC) voltage source, but what we commonly find are voltage sources of alternating current (AC). In order to achieve a direct current voltage source, the alternating current input must follow a conversion process.

Voltage regulators (linear, switching) provide a stable and fixed voltage output to give energy to electronics circuits from an unregulated power source

Current Limiter circuit for a Power Supply using a transistor and a resistor.

If the load current exceeds its maximum, an over current protection is needed

Explanation of a transistorized voltage regulator. Zener diode and transistor voltage regulator circuit diagram

This full wave rectifier requires a center tapped transformer. This additional end on the secondary winding of the transformer divides the voltage in this winding into two equal voltages. The additional end is grounded.

The half-wave rectifier rectification process. Polarization of semiconductor diode in the forward and in the reverse direction. Input and output waveforms

This circuit is designed to connect to a specific circuit because it can only provide a maximum and minimum current.