Delete comment from: Ken Shirriff's blog
Ikem: thanks for pointing out the typo. I'm glad you weren't complaining that MOSFET transistor is redundant :-)
Technician: there are two grounds - a high side ground, and a low side ground - and they are not connected, so a failure of D4 won't put mains voltage on the output. The ground on the first page of the schematic is different from the ground on the second page of the schematic. I should have used a different symbol to make it clearer.
Anonymous: the ceramic Y capacitor is designed not to short out. The point of a Y capacitor is it is designed to be used in a role where shorting out would shock the user. I believe it would have 240V AC across it (for half the cycle), which is within the rating.
Anonymous: I didn't think anyone actually read the footnotes, but you're right - the capacitor is 220pF. I did get it right on the schematic though.
Jul 29, 2013, 1:31:12 AM
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