Full bridge rectifier

207

03:45:10

I got the voltage regulator part of the circuit form the internet, but clearly it isn't good because the current through the zener diode shoots up to 150mA, enough to destroy it over extended use. Can you suggest a better voltage regulation circuit?

published 8 years ago

thebugger

8 years ago

You must've copied it wrong. Usually these circuits work (even though they're quite dangerous)

tonyinselby

8 years ago

A few points: First, your mains voltage is too low. 220 V mains is 220 V RMS. The simulator amplitude of an AC waveform is the peak value, which is RMS × √2, or about 310 V for a 220 V RMS supply. This, of course makes your problem worse. However your dropper capacitor is far too large. Try about 680 nF for a 310 V (peak, 220 V RMS) supply. Finally I'd increase the discharge resistor to more like 68 kΩ, just because. And as @thebugger says, circuits like this are dangerous; one side of the load is connected directly to the mains. A lot of cheap kit from the Far East is wired this way, but that doesn't make it any less dangerous.

tonyinselby

8 years ago

Oops, forgot. I'd also use a 660 Ω - 1 kΩ resistor to supply the Zener.

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.