Posted to alt.binaries.schematics.electronic,sci.electronics.design,sci.electronics.basics
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AC Cap Dropper DC Power Supply
On Wed, 03 Oct 2012 22:23:50 -0400, Jamie
t wrote:
John Larkin wrote:
On Wed, 03 Oct 2012 15:39:58 -0500, John Fields
wrote:
On Tue, 02 Oct 2012 11:08:51 -0700, John Larkin
wrote:
On Mon, 01 Oct 2012 18:03:56 -0500, John Fields
wrote:
On Mon, 01 Oct 2012 08:34:46 -0700, John Larkin
wrote:
On 1 Oct 2012 06:00:24 GMT, Jasen Betts wrote:
On 2012-09-30, John Larkin wrote:
The series current-limiting cap dissipates no power,
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Not quite true, since no dielectric is lossless.
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so it can be shorted by a low voltage switch.
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It can be but, depending on when in the cycle the switch turns on,
things might get grim.
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If it drives, say, the input of a
bridge rectifier or a 2-diode restore thing, short the input of that.
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Still, depending on when in the cycle the switch turns on, things
might get grim.
Bad engineering can create grim outcomes. Better to not do that.
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It becomes a bang-bang regulator. If the controller is to be a custom
IC, a modest amount of complexity is free, so some intelligent
zero-crossing thing would be appropriate. But just dumb bang-bang
ought to work.
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From the ridiculous to the sublime to the ridiculous!
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This is one variation:
https://dl.dropbox.com/u/53724080/Ci..._regulator.jpg
inrush current will destroy it.
As I mentioned, and you snipped, people often include a series
resistor to limit transient currents.
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And yet your circuit shows that some people - who should know better -
don't.
Idiot whining again. That's pretty much your skill set.
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I'm the idiot???
You claim that people often include a series resistor to limit
transient currents and yet, the circuit you show - which seems to be
susceptible to damage from transients - doesn't include the resistor
you claim should be there.
I said in plain English that a series resistor might be appropriate.
In some cases, like a clean low-voltage AC source, it might not be
needed. I've done lots of voltage-doubler type supplies with no series
R.
incandescent lamp in series, drops back down to low R afterwards, keeps
every one happy
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JF
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