Voltage converter (continued)

rectifier 230/12

hi again;

I think it does not matter whether conversion from AC to DC.

The exact thing that I need is a capacitive- resistive circuit which converts 220V to 5V. Please help me..

thanks..

I think u have to use a step down transformer and den u can use a capacitive-resistive circuit for low pass filter and den for regulation u hav to use REGULATOR IC

Transformer - No centre-tapped (shown below). Look for 240/12, 230/12 or 220/12 transformers. If you can find 240/9, 230/9 or 220/9, it would be fine too.
If you use a transformer with centre-tapped, you can instead use a full-wave rectifiers (using 2 diodes only), the centre-tapped terminal of the transformer is your circuit ground.

Rectifier - Bridge rectifier (shown as 4 diodes below). You can buy it in a round or rectangular package with 4 terminals (4 long metal pins).

Smoothing - Electrolytic capacitor used for smoothing. Most people use 2200 to 1000µF, but 1000µF is good enough because you don't really need to store a large charge to hold a higher DC voltage, in your case 8V is good enough. Assuming you are using 240 or 230 or 220/12 transformer. It would be good to add 2 more capacitors in parallel to this 1000µF with values like 470 or 330µF and then with 0.1µF.

Regulator - Linear Voltage Regulator LM7805 or LM2940 to regulate from input 8V to output 5Vrms DC. Add a 0.1µF capacitor in parallel to the 5V output.

hi
if isolation is not important,u can use two Cap. to build voltage divider . Use polyster type.
Use of a zenner regulator improve regulation.

I have this circuit and we tested it,.. But, there are many precautions you should taqke.
1- Load is always constant. Changing in the load can damage the whole world.
2- The capacitor used must have high voltage rating.
3- You have to put the dummy load which is the resisance and a LED.
Finally this is on your own risk.