Arduino SMPS with ZCD

I am working on a project and i am planning to use arduino as a standalone, i have designed a SMPS (5v-1.5a) circuit along with Zero crossing detector as shown in following image.

i haven't decided the component values yet. I need your suggestion weather the circuit is fine or do i need to change anything?

Thank you!

Where did you get this circuit and what is your experience ?

The design of a SMPS is not trivial.

Layout on the pcb can be critical.

Also probably a lot cheaper and safer to buy a ready made unit, either the wall wart or chassis types.

The secondary caps negatives and opto pin2 have to be connected to ground.
There is no feedback circuit for the mosfet, so the circuit won't oscillate.
It's just an expensive smoke bomb.
Take the advice from the other posters, and don't play with AC unless you know exactly what you're doing.

Forgive me for asking but where is the SMPS OUTPUT ? (What did you plan to connect to the point labeled "Vin") (Is that your way of labeling Vout ? (Vin ?)(on the secondary side)


Tom... :slight_smile:

It looks like a dogey SMPS that would be in one of those spontaneous combustible USB chargers.
Feedback is via OK8, as DC output gets over Zener D3 voltage the gate is shorted to drain.
Somehow it is kickstarted to got in the first place.

What is your supply voltage?
What is your transformer?
What are the component values, especially the electrolytic caps?

Please do not cross-post.

Tom.... :slight_smile: