I'm in the middle of making a small mechanical device, and I need to locate 3 momentary switches to control what parts of it will recieve power. Out of my 3 momentary switches, when one is pressed, I only want one rail to be powered at any given time... much like a 3 way toggle switch I suppose. (If one of the switches is accidentally held down while another one is pressed and released, what would happen? Would the new press override the held-down button) for the more visual people I drew an mspaint: The left ground is not necessary, unless its required for the chip, or whatever is recommended for this.
well, after a lot of googling different terms I believe I've found what I'm looking for. Can anyone interpret this datasheet: http://www.jameco.com/Jameco/Products/ProdDS/321761ELAB.pdf I'll call jameco tech support tomorrow if nobody responds, thanks in andvance to anyone who does
That chip is basically 8 latching circuits in one. Each channel operates individually. Hold on a bit and I can mash up a circuit with 555s until cpemma or someone comes along and has a better idea.
When switch 1 is pressed Output 1 switches on, the other two switch off (or stay off), When switch 2 is pressed Output 2 switches on, the other two switch off (or stay off) etc. It can be extended to more if needed. You may also want to add a switch to turn all of hem off (Just have the switch to all the pin 4s (reset) and ground) As for holding a switch down, that will override any other button presses until it is released Any questions just ask.
Thank you r4tch3t, this easily solves my problem. In fact, by looking at what you've put together I could narrow it down to one 555. Reading up more on 555 timers (this is my first time messing with them), could I solve the problem of a held down momentary switch by integrating a monostable 555 that outputs a pulse?
I've read about it, is it absolutely necessary as I'm not doing any type of counting or numerical applications? What method of debouncing should I use if that's the case...
De bouncing is not needed for the above circuit as repeated presses do nothing, just like holding it down. A button press makes the output go high thus turning the transistor on and therefore the circuit. How are you thinking of using one 555? Because as I see it with this particular configuration each 555 is responsible for a "high"state for each output.
I'd have to make a whole animation I think to explain what's going on with what I'm trying to make. I'll try to draw up a diagram when I get off of work.