5 volt power supply

Circuit components & Working:-

Transformer:-

·         Transformer used here is step down transformer. It used to reduce the 230V (AC) voltage coming from line to 18V (AC).

·         Frequency remains unchanged.

·         We put primary of transformer into AC line coming in our home.

Bridge Diodes:-

·         After reducing AC voltage its further given to the bridge rectifier to convert into pulsating DC (not pure DC).

·         Diodes allow to conduct in one direction only this property of diode helps it to convert the AC into pulsating DC.

·         During a half cycle only two diodes conduct.

·         In one half cycle current flows through D1- Load-D2.And in another half cycle current flows through D3-Load-D4.(Here load is not connected we connect load to o/p terminals ).

Capacitor C1:-

·         Capacitor C1 is filter capacitor.

·         The filter used in this power supply is Capacitor filter.

·         Capacitor is connected in parallel connection here.

·         Reactance of the capacitor is very low to the high frequencies so the high frequency components are filtered out by capacitor to ground. Capacitor acts as a short circuit to the high frequencies and blocks the DC current.

·         So the DC current is passed through 7805 regulator to further increase the stability of the power supply.

7805 Regulator IC:-

·         LM7805 is regulator IC.

·         It increases the stability of the power supply.

·         That means the power supply gives the constant output for different load condition. That is to heavy or light loads.

·         Capacitor C2 is capacitor used to increase the stability of 7805 further. It is recommended by manufacturer of Regulator to add it.

·         Output Current up to 1A.

·         Output Voltages of 5V.

·         Thermal Overload Protection

·         Short Circuit Protection

·         Output Transistor Safe Operating Area Protection.

R(330 ohms):-

·         It is a current limiting resistor, used to limit current flowing through the LED.

LED:-

·         It is used to check whether any dc power is provided.

·         If dc output is less than 3V then LED will not glow.
        Click to download the files.(pcb layout opens with Express PCB software)
         DOWNLOAD 





.....for any Queries type below
c