What are regulated power supplies for?

Question

We are planning to construct a current and voltage regulated power supply as our project,but in our wright-up we should determine first what are the specific usage of our device and to what certain applications can it be used?

Answer 1

Regulated PSU are used for many devices which require a percise power source (as in one that has very little drift) or lack their own internal regulation system. It is mostly used for sensitive circuits that use IC's and other delicate components.

Answer 2

A regulated power supply has two purposes:

1.  Keep the supplied power below the noise level.  Example: The FM tuner section of your car's radio is probably operating at about 6 volts (well below the 12 volt power level of the car).  If it operated at 12 volts, the noise from the alternator and spark plugs would interfere with your listening enjoyment.

2.  Keep the supplied voltage constant over a wide range of power levels.  Example:  The power supply in your computer supplies several voltages ( 5 volts, and plus and minus 12 volts).  The computer's power supply is holding considerable power in reserve so that these voltages won't drop when a hard drive or CD drive suddenly kicks in.

Here is an idea for your project: Take a small battery-operated AM radio and run it from a hand-cranked DC generator.  That should cause the radio to make lots of noise when listening to a weak radio station.  Then put a simple 3-pin regulator chip between the generator and the radio.  The generator noise will disappear.