The schematic is spot on, thanks.Haven't heard of the node thing before but I'm guessing it's just the groups of leads that are connected on a trace area.
620nf cap, voltage dropper
The zener normally will only conduct in the reverse direction but will clamp the voltage to a safe level if the LED blows open.
Are you sure? If I understand your explanation right the Zener is "only" for protection. So the circuit would work without it as long as everything is OK. But I think the Zener will be conducting in forward mode while Mains 2 has higher voltage than Mains 1 - there must be a way to discharge the 820 nF cap faster than 500k resistor. Or am I wrong? AC is a bit difficult to understand for me.
I'm pretty sure the cap does charge to almost full line voltage. 820 nF is 3.2kohm of reactance at 60 Hz, which easily overwhelms the impedance of the Zener and 100 ohm resistor. It's probably got 100V RMS on it. I'm pretty sure it was rated for 400V.And we don't necessarily know what production factors went into the design. 3 extra 1N4007s would take up quite a bit of space, and there's already not much in there. The box is literally just as big as it needs to be to to hold the board and cap. On Digikey I only saw a few cents difference in the unit price between the 820 nF and 470 nF version, but Digikey only goes up to 2,500 quantity. Components for cheap things like these are probably bought by the 100,000s, and I have no experience with production quantity component sourcing.
I would highly doubt the 'next' design will have a bridge rectifier, as it just so happens that the 'previous' design that was using a 5mm bulb type LED had one. So in essence, they've unimproved to trim component count if you think a bridge rectifier is an improvement.
Hi,When it came to the charging issue, i was talking about the electrolytic. Try reading my last post over again. I also stated that the smaller cap had to have a high voltage rating so i dont see how you could have confused these two.
But hey we could look at other designs too if you like. I had one up on my website before the dang company killed that part of their services. Many i'll have to start another one of these days :-)
...modify one to add a button to shut it off in the dark, but still turn back on automatically after a light-dark cycle.