The 408 is inexpensive, but requires a fairly large and costly AC rated
capacitor.
The 409 is only a bit more costly, and is already on a PO here - the input
diode is cheap, as are the output cap and either zener or divider R's.
Good-bye $$8.00 transformers!

The 408 must be very common in commercial controller designs. I have
questioned support people regarding the 285V input limitation stuck on a
number of AC powered process controllers - and nobody ever had an
explanation. Since this # matches the input limit of the 408, perhaps,
voila!

C

>  >>Just come across some linear voltage regulators
>  >>from ST Microelectronics called VB408 and VB409.
>  >>They have a high input voltage range (400 and 580V),
>  >>so they can be connected directly to rectified 110
>  >>or 220 V mains. They deliver a max of 40 or 80mA, so
>  >>could easily feed a simple PIC circuit.
>  >>http://us.st.com/stonline/books/pdf/docs/6421.pdf
>  >>http://us.st.com/stonline/books/pdf/docs/6941.pdf
>
>      I haven't used this wondies yet, but it seens great. I
> hope to buy
> some of then very soon to make some tests. It seens the ideal solution
> for powering some small gadgets I'm still working on.

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