SMPS AC to DC no transformer

537

10:10:18

This SMPS (Switching-Mode Power Supply) only uses a diode bridge, some resistors, a few capacitors and a NPN-transistor to convert 230VAC (rms) to 4VDC with a current of 15mA. This SMPS is dangerous to use! It has no isolation of the input voltage via a transformer. It can bite, when something goes wrong.

published 7 years ago

PrathikP

7 years ago

What makes you think that this is an SMPS? It is just a regular low-power capacitor dropper power supply.

PrathikP

7 years ago

And it looks like you are using a transistor shunt regulator along with a zener shunt regulator. Why two shunt regulators?

PrathikP

7 years ago

I tried to make an SMPS a while back with the limited components available. http://everycircuit.com/circuit/6221336497356800. A flyback switching power supply must look something like this.

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