RS-232 Tx / Rx monitoring LEDs?
cclist at sydex.com
Sun Aug 23 10:56:52 CDT 2015
On 08/22/2015 11:55 PM, drlegendre . wrote:
> I've also seen C-R series voltage dropping circuits, here & there.
> Correct me if I'm wrong, but doesn't the series cap dissipate power
> just as it would, were it a series resistor? I mean, if the LED is
> passing 20mA, the cap is also doing 20mA - and at whatever the Vdrop
> Right? If not, why?
That's correct--but there's the matter of the voltage. Eventually,
you'll see that the brightness of the LEDs will drop fairly rapidly
before the thing is useless. A common dodge used by Chinese
manufacturers. Saves a few components, doesn't it.
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