I don't know if there was a question attached to
this diagram but -
1. This is a valid way of
measuring mains zero crossing but be aware of
the potential for electric shock.
2. The TITLE suggests that this is both a
power supply AND a zero crossing detect circuit.
It looks like those are 2M4 resistors.
If used for a power supply the current available will be
inadequate (about 230*1.414/4M8 /2 = 24 microamps.
I assume that it is therefore only for zero crossing
detect.
A power supply COULD be arranged by this means with smaller
resistors but the Vcc rail MUST then be clamped with eg a zener diode to prevent
it being pumped up to excessive voltages.
All in all a wee bit of a risky circuit - best not to use
unless there is a good reason to.
Russell
McMahon
_____________________________
(* - or woman, child or internet enabled
intelligent entity :-))
i am new to pic micros but i read this in the
beginers guide to the microchip pic hope it
helps