The small AC to DC Voltage Converter project uses four diodes to make one bridge rectifier to transfer AC power to DC power. Also, we use capacitors to remove ripples in the circuit. After we transfer from AC power to DC power, we need to use one 5v voltage regulator to give 5v DC output from 12 v DC output.
In this project we choose a 12VAC 20VA transformer with screws at the bottom. In order to power the circuit with this transformer, we have to screw the jumer wire pin inside and plug to the breadboard. Because this is an AC power supply, the positive and negative side does not matter.
Step 2: Build the Bridge Rectifier With One Capacitor in Parallel With It
In this step, we build an bridge rectifier which make up of four 1N4001 diodes. Then, we parallel this rectifier with an 1000uf parallel to remove some ripple. The thing need to be noticed is the polarity, remember the silver line on the diode indicates that it is a cathode terminal. After finishing building, please use mini voltage display to test the voltage across the capacitor. It will give you an around 18v DC power.
Step 3: Add the Voltage Regulator to Give 5v DC Output
In this step, we need to use the 5v IC Regulator, one 0.1uf ceramic capacitor, one 0.22uf ceramic capacitor and one 1000uf electrolytic capacitor. For the IC regulator, with the lead on the bottom, the left is input, the middle is ground and the right is output. After finishing building the circuit, you can use voltage display to test the output voltage by paralleling it with the last 1000uf capacitor. You will see the output is 5v DC.
Step 4: Future Improvement
In this project, we can only have a 5v DC output. However, we can try to figure out output any voltage from 0v to 12v DC. This can be solved by replacing Voltage regulator 7805 with a variable voltage regulator LM317.