>> B) A capacitive dropper would not provide enough current to drive the uC
>> and a two digit 7-segment display. A straight zener type arrangement wou=
ld
>> waste too much power.
>=20
> Remember that this is an electric heater that is already "wasting" 1kw+ o=
f
> electricity as heat. There is no requirement for any part of the circuitr=
y to be
> efficient as any extra heat produced by the control circuitry  would cont=
ribute
> to the purpose of the heater.

True, but he said it is a European originated item, and Europe has regulati=
ons about maximum current draw allowed in the 'off' state where there is co=
ntrol electronics in the always on state. This is why ST and others have ma=
de the tiny switch mode chips which draw such miniscule power with no load =
that under the regulations they are considered to draw no power.
--=20
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--=20
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