In laboratory and experimental work, the source of electric energy is very mportant for the project. Most electronic products require power to function so power supplies are an integral part of any instrumentation system. Sometimes it is difficult to use a power supply when it comes to getting an accurate output value and often the more features on the power supply the more difficult it is to operate. When a power supply has all these different features they also become expensive to purchase.

The programmable power supply (PPS) that I am designing will have several advantages over a typical power supply since it will eliminate the problem of trying to get an accurate output value, it will have fewer features making it easier to use, and a smaller size. The size of this power supply will make it easier to carry and it will save space in the working environment.

Source: http://powersupplycircuit.blogspot.com/2009/01/programmable-power-supply.html