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Transformerless Power Supply Help

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By including two smoothing capacitors (with resistor in between), it reduces stress on components. Smaller watt values can be used.

This is the most reasonable solution consistent with the original requirement. However, I believe that the values are not optimized and the actual values can be tweaked for the desired output.

A high value resistor (say 100K- not computed) may be connected in parallel with C1 and a surge protector may be used for better performance.
 

The circuit looks very close to useful, optimisation would be lowering the power in the R's and using the least sized components, however if the supply has to work over 200 - 265Vac - then there will be penalties to pay in both these areas...
 

Hi Brad, how many volts on C2? what is the power in R1, R2 ...?

You must always have a zener on the output to limit Vrise ( on the caps ) if the load is taken away ....

This is the most reasonable solution consistent with the original requirement. However, I believe that the values are not optimized and the actual values can be tweaked for the desired output.

A high value resistor (say 100K- not computed) may be connected in parallel with C1 and a surge protector may be used for better performance.

This is my revised schematic with your recommended improvements.

230VAC cap drop dio bri 2 RC filters 2 zeners 5VDC load 50mA.png
 

A perfect circuit diagram will really help people. Not only me but most of the person who works with electronics. Sometimes we need small circuit in small size, this will really be helpful if we all try to solve the problems and can make a best circuit.
 

So this circuit is the most recommended I think. Please share your opinion if I'm missing anything.
Capture.PNG

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Is this necessary to add a diode 1N4007 across the Zener Diode in parallel to reduce forward current through ZD?
Like this:
Capture.PNG
 

So this circuit is the most recommended I think.

No.

I strongly recommend the circuit in post #23.

Without doing any detailed analysis, try to figure out "qualitatively" the positive features of the circuit. Look for features and you will suddenly understand.

Although it uses more number of components, it has some robustness designed into.

Compare it with the two in post #25 and you will know what I am saying!!
 

It depends on whether the 0v needs to be connected to neutral or not ....
 

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