Voltage Regulator Circuit

Generally, a voltage regulator circuit will consist of at least five components. These will include a power source, diode(s), resistor(s), diode(s), transistor(s), and capacitor(s).

A general description of a voltage regulator circuit follows. Prior to the power source being connected, all the components of the circuit should be grounded at 0V.

When considering the operation of a circuit without a capacitor, voltage will flow through the diode and should be held constant. The voltage will then cross to the transistor and the series load resistor.

Due to the volume of the voltage, the current flows from the diode into the base of the transistor. This causes the voltage through the resistor to remain constant if the diodes are forward directed.
To understand how this circuit will be able to succeed in maintaining the voltage evenly across the load, one should remember how the current is conducted in the circuit. The current flowing is dived amongst the diode and the transistor.

The capacitor is a circuit element that stores electrical charge. It is often used various circuits to help keep the output voltage of a voltage regulator constant over periods of time. A formula for the changing rate of voltage through a capacitor is directly proportional to the current output, sub-divided by it’s capacitance. So, the larger the capacity of the capacitor, the smaller the resulting changes in voltage will be at the fixed current drain of the output of the regulator over time.