Re: 12V regulator

On Mon, 20 Oct 2008 17:17:10 -0500, Steve wrote:
On Mon, 20 Oct 2008 19:18:16 GMT, Rich Grise <rich@xxxxxxxxxxx> wrote:
On Mon, 20 Oct 2008 01:59:51 -0400, Paul E. Schoen wrote:
"Steve" <s@xxx> wrote in message
...
led switch, but it's proving a bit more difficult than I wanted for
this particular application. Thanks for the replies,
Steve

You should be able to use about a 10k resistor (about 1-2 watt), and a
1N4004 or higher rated diode, in series with the LED.

It's not necessary to put a diode in series - the LED is alreaady a diode.
But it _is_ necessary to put a diode in antiparallel with the LED so its
reverse voltage stays belos its limit.

But the OP has already said that he doesn't have access to the resistor/
LED junction, so he's just going to spring for the neon switch.

So, would putting the diode in reverse across the switch terminals not
provide enough protection for the LED? Thanks for all the help,

Now that you mention it, yes - the other diode will clamp the voltage
across the resistor/LED series circut, which will serve the same
function as only clamping the LED - i.e., very limited reverse
voltage.

And don't forget the series resistor! :-)

Have Fun!
Rich

.

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