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I have very basic knowledge of electronics.

I am looking for a circuit which can turn ON/OFF an LED from a single switch.

  • If the LED is OFF and the switch is pressed (even if not released) then the LED should turn ON.

  • If the LED is ON and the switch is pressed (even if not released) then the LED should turn OFF.

A switch can be a push to ON switch but turns OFF when released. It is not like a toggle switch.

Thanks in advance

Amit Kumar
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  • What parts are available to you? Would a D-Flip Flop work? – Tyler Oct 21 '15 at 02:29
  • Hi Tyler, I have 555 timer IC but can get other items as well. Just need a really simple solution to achieve this. – Amit Kumar Oct 21 '15 at 02:34
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    Your solution is right here. It's called a "Soft Latching" power switch. Check it out – ezra_vdj Oct 21 '15 at 04:12
  • @ezra_vdj If the button is not released then the circuit will oscillate; the LED will flash. – CharlieHanson Oct 21 '15 at 11:35
  • @CharlieHanson If it's good enough for Dave Jones I'd say it's good enough. All depends on project, cost, who's using it etc though, you feel? – ezra_vdj Oct 21 '15 at 11:41
  • @ezra_vdj The OP implies that oscillation is not acceptable with "pressed (even of not released)". It may be good enough for Dave Jones - and plenty of others as this is one of the oldest tricks in the book - but if it violates part of the specification then it is not the solution. – CharlieHanson Oct 21 '15 at 12:34
  • Yep I don't want a flashing LED. Anyways thanks everyone for your time and help. I thought it will involve few components but I don't think there is any such design. I have to manage 10 LEDs and these designs will make my project bulkier. I have to find something else then. – Amit Kumar Oct 21 '15 at 23:32

1 Answers1

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This one is fairly simple: -

enter image description here

Each time you press the button, the output latches in the opposite sense to what it previously was. Lots of good ideas.

Picture stolen from this stack exchange question: Make a Latching Relay using SPDT Relays

Is this question all but identical?

Community
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Andy aka
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  • Thanks Andy. The circuit looks OK but will not fit my project as I have to manage multiple LEDs. May be 10 or something. Do you have any suggestion? – Amit Kumar Oct 21 '15 at 23:34
  • Here is my exact requirement. http://electronics.stackexchange.com/questions/196598/circuit-to-indicate-1-to-10-based-on-pressed-switch-non-latching – Amit Kumar Oct 22 '15 at 00:09
  • I have answered this question for a single channel. Just step and repeat for multiple channels. I don't see the problem unless, of course, you have changed your mind about what you want. – Andy aka Oct 22 '15 at 09:21
  • I haven't changed my mind. I was looking for a circuit with less number of components. However, your answer seems to be more accurate than others. Thanks for your help. – Amit Kumar Oct 22 '15 at 23:26