Comments on: Momentary Button as On/Off Toggle using 555

By: Colin Mitchell

Colin Mitchell — Sat, 21 Apr 2012 17:59:02 +0000

If you fit a 2k2 between base and 0v, the transistor will always turn off.

By: Colin Mitchell

Colin Mitchell — Sat, 21 Apr 2012 17:58:18 +0000

If you fit a 100n across the upper 10k resistor, the chip will always turn on in RESET mode.

By: kerps

kerps — Sun, 01 Apr 2012 21:49:59 +0000

hi :) great little circuit.

ive been trying to replace the button with a transitor or an opto isolator. So the latch can be triggered from a logic 1.
i wonder,has anyone any ideas what part could replace the manual switch?
: P

By: Robert

Robert — Mon, 01 Aug 2011 10:41:50 +0000

This is exactly what I’m looking for but is it possible add one more push button for reset??? I mean- if circuit is switched on reset push button will all the time reset circuit and circuit stay off

By: Gijs

Gijs — Mon, 06 Jun 2011 12:57:39 +0000

Never mind, I found this website:

http://www.bowdenshobbycircuits.info/page9.htm (chapter: “Relay Toggle Circuit Using a 555 Timer”)

Thanks anyway!

By: Gijs

Gijs — Mon, 06 Jun 2011 11:55:08 +0000

perfect circuit! I was wondering if it’s possible to power it with a 12V power supply, the datasheet states that the 555 can operate at 15V…, does anyone know??

By: Tal Ofer

Tal Ofer — Tue, 17 May 2011 06:36:03 +0000

THANKS!!!

I’m a beginner, and doing an ardiuno project. for the project I needed 12v (for the arduino) 5V for a relay and 3.3 for a lcd screen backlight. so I ended up using a ATX power supply.
So I took your sketch and used the 5Vs.b. to “short” the 3.3V sp-on ….
So now I can switch the ATX on by the momentary push button … HAPPY :)

Thanks again, great post

By: Fredrik

Fredrik — Tue, 19 Apr 2011 07:54:07 +0000

This is exactly what I’m looking for!
Thank you! :)

(iMac G5 20″-hack into a standalone monitor – view my webpage).

By: todd

todd — Thu, 31 Mar 2011 16:55:47 +0000

i have found that using a 3906 transistor as opposed to a 3904 transistor works exactly as in the video. i had no success getting the 3904 to turn the led off. i popped a 3906 in and it worked just fine.

By: moralinverter

moralinverter — Wed, 22 Sep 2010 18:05:59 +0000

Hi,
Is there a 555 timer circuit which can toggle between three different states. If yes can you please post the links. It will be really helpful for me.
thanks
moralinverter

By: ThatGuy

ThatGuy — Sun, 19 Sep 2010 18:48:50 +0000

Just curious if there is a way to also keep the timer function, as in – press once, circuit is on for 1 hour then turns off or turns off immediately if pressed again while on.

By: SiliconFarmer

SiliconFarmer — Fri, 23 Jul 2010 19:16:00 +0000

Gumby,
Disconnect pin 4 from +5V. Put a 10K resistor from pin 4 to +5V and a 0.1uF capacitor from pin 4 to GND. That will give the circuit a short reset pulse when power is applied.

By: gumbydammit

gumbydammit — Fri, 16 Jul 2010 13:17:16 +0000

I was wondering, do you know of a way to make sure the circuit is always defaulting to “Off” when you power it up? I have the circuit working, but when I initially turn on the power supply I get the LED on sometimes and off sometimes, even though I have been making sure the circuit is in the off position when I power it down. I’d like this as a safety feature, but I lack the insight into that problem. Thanks in advance for any information and thanks for posting this. As a newbie I really needed to see the circuit in another form besides the schematic to make heads or tails out of it.

By: shanemag85

shanemag85 — Sat, 12 Jun 2010 11:13:30 +0000

now ive managed to get this working however i cant seem to get this to pulse aswell, is this possible?
Basically i want this so when the tactile switch is pushed the led will flash rather than stay on.
cant seem to get it to work

By: Wiley Wiggins

Wiley Wiggins — Fri, 19 Feb 2010 18:42:41 +0000

Yay! You rule! I’m going to start cranking these out after next month. Right now I am up to my eyeballs in VDMX (http://vidvox.com). By the way, if any of the geniuses on this blog can work out a way to have a MaxM change to a random color every time it senses a whack with an accelerometer (all on an arduino), I will pay you for your design! I want to have a kickdrum light up a different color every time it is hit.