A voltage regulator is a device that maintains the voltage in a circuit at a specified level. A passive voltage regulator limits the voltage to a particular maximum but has no effect if the voltage is already below this maximum. An integrated circuit (IC) voltage regulator is a common passive regulator and may be purchased in bulk quantities from an electronics supply store. You can easily install a voltage regulator into a simple circuit to demonstrate its function.
Instructions
1. Identify the leads on a 7805 voltage regulator. Position this voltage regulator so that you can read the printing on the top. The lead on the left is the input, the lead on the right is the output and the lead in the middle is the ground for the voltage regulator.
2. Build a very simple circuit without the voltage regulator. Connect the battery holder's negative terminal to the light bulb's negative terminal with electrical wire. Similarly, connect the battery holder's positive terminal to the light bulb's positive terminal with electrical wire.
3. Place the voltage regulator into this circuit. Remove the electrical wire from the light bulb's positive terminal and connect it to the input lead of the voltage regulator. Connect the light bulb's positive terminal to the output lead of the voltage regulator.
4. Connect the ground lead of the voltage regulator to the common ground of the circuit. In this circuit, the common ground will be the wire that connects the battery holder's negative terminal with the light bulb's negative terminal.
5. Insert the battery into the battery holder to complete the circuit. The light bulb will only receive 5 volts even though the power supply is a 9-volt battery. A passive voltage regulator like a 7805 simply dumps the excess voltage as heat.
Tags: voltage regulator, light bulb, battery holder, negative terminal, positive terminal, voltage regulator
