Regulated Power Supply
A regulated power supply is an embedded circuit; it converts unregulated AC into a constant DC. With the help of a rectifier it converts AC supply into DC. Its function is to supply a stable voltage (or less often current), to a circuit or device that must be operated within certain power supply limits. The output from the regulated power supply may be alternating or unidirectional, but is nearly always DC(direct current).
The major blocks of power supply are given below Transformer, Rectifier,Filter , 7805 voltage regulator.
The output of filter is not constant output voltage it will varies according to changes in input but we want constant output voltage. For this purpose we are using voltage regulator.