Transformerless Power Suppply

[nomada]

Hi,

Be carefull, be very carefull, when using a power supply without transformer is like walking in the wire without the net underneath...

Atached you can see the circuit I use to put some power ... in PICs and other stuff. I found this circuit some years ago when I bought a kit (K6713)from Velleman, its a IR receiver to switch on/off a load connected to mains trough a relay.

One more advise, if by any chance you are planning to use this circuit in a touch sensor or similar do not forget to use two resistors in series for the sensor, the contour voltage for a regular 1/4W is less than 200V, unless you like to get a curly hair...

regards

[Melanie]

If you're still looking for components, attached PIC I've taken gives you an idea of what to look for... The 11V VDR is pretty small (VDR2 in this pic) - and also laying alongside with a view of a typical Capacitor you can use. If it's an X2 type you're OK, otherwise you'll have to fit one with a 400vDC rating. It's a real good idea to absolutely and positively mark the PCB that it's LIVE... even if it's just for yourself. Some time in the future you'll forget and it'll bite you.

[ERIK]

Thanks Mel, I have finally got some 275V X2 caps and some VDR's (I had to buy 100 of them but thats OK). So I'll sort out a PCB (well marked, and well housed) and let you know how it goes...

[sayzer]

Hi Melanie,

Going back to this post,

Would that be too much to ask for your complete fan controller schematic?
and, if possible, for the code also?

I am having a similar inquiry and would like to see your approach.
Or if there is anyone else who had a similar design.

Regards

[Melanie]

Hi Sayzer

This product is still in volume production (about 1000/month), and I'm treading on thin ice just posting the PCB view (a couple of posts above) and some snippets out of the PSU schematic - the remainder if you're clever you can figure from most of the components in use and eliminating those I've already revealed... a licence for the complete Software and Schematics would cost... I envisage around $5K.

Melanie

[sayzer]

May be, I can support that thin ice, so it will not crack.

Since you already have it in production, I may need not to work on it;

This is of course if you are able to sell it to other customers. Are you?

Should I PM to you?

[Melanie]

Sure, continue this by email, as I can then send you the product Datasheet so you can see if it fits your requirements.