Re: Anybody Seen a Simple LED "Fail-Over" Circuit ?

From	rbowman <bowman@montana.com>
Newsgroups	comp.os.linux.misc
Subject	Re: Anybody Seen a Simple LED "Fail-Over" Circuit ?
Date	2024-11-26 08:40 +0000
Message-ID	<lqlfrpFu455U1@mid.individual.net> (permalink)
References	<ywWdnVFGrNEA6tj6nZ2dnZfqnPSdnZ2d@earthlink.com>

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On Tue, 26 Nov 2024 02:24:12 -0500, 186282@ud0s4.net wrote:

> Critical Redundancy - One LED fails, another takes over ?

Complicated question. For a complete catastrophic failure where the LED is 
either open or shorted  a couple of transistors might do it. Even that 
would be difficult if a PWM dimmer is used.

Even worse the degradation may be light output and/or color rather than a 
simple go / no go.

Then you get into the human part of the equation:

https://learn.sparkfun.com/tutorials/light/visible-light

I'd actually been playing with PWM output in a Pico with C. The Uno piles 
a lot of sugar on it with analogWrite rather than the Pico SDK 
hardware_pwn

https://cec-code-lab.aps.edu/robotics/resources/pico-c-api/
group__hardware__pwm.html

I've got to play with it a little more but simply incrementing the duty 
cycle isn't too smooth perceptually.

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Thread

Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-26 02:24 -0500
  Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? rbowman <bowman@montana.com> - 2024-11-26 08:40 +0000
    Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-27 00:05 -0500
  Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? Bernd Froehlich <befr@eaglesoft.de> - 2024-11-26 09:00 +0000
    Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-27 00:20 -0500
  Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? Rich <rich@example.invalid> - 2024-11-26 13:34 +0000
    Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? not@telling.you.invalid (Computer Nerd Kev) - 2024-11-27 08:21 +1000
      Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? Rich <rich@example.invalid> - 2024-11-27 01:26 +0000
        Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? Computer Nerd Kev <not@telling.you.invalid> - 2024-11-27 15:12 +1000
          Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-28 03:11 -0500
            Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? not@telling.you.invalid (Computer Nerd Kev) - 2024-11-29 07:06 +1000
              Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-29 05:53 -0500
    Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-27 00:36 -0500
      Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? Rich <rich@example.invalid> - 2024-11-27 06:47 +0000
        Re: Anybody Seen a Simple LED "Fail-Over" Circuit ? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-11-27 23:47 -0500

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