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Novice circuit design question?
How can I set something up on a breadboard that will turn on an LED for 10 seconds when I tell it to? I have kind of been playing around with 555 timers but am completely and utterly confused, so I thought I would ask you guys. Should I use a 555 timer or some other ic? Or is there a simpler way to do it?
Thanks
2 Answers
- FanshaweLv 61 decade agoFavorite Answer
You can use a 555 timer to do the job.
Alternatively, if you are not too concerned about the accuracy of your 10 seconds, you can drive your LED using passive components only.
I.e. Charge a capacitor through a series resistor and diode.
Then discharge the capacitor through a second resistor connected in series with the LED via a push button switch.
The diode in the charging circuit will prevent the capacitor discharging back into the voltage source.
You know that the time constant of a circuit containing resistance and capacitance is R x C, so you can use this to calculate the values of R and C to obtain 10s illumination.
Good luck!
- Paschal HLv 61 decade ago
A 555 should do well, as long as the current needed isn't too great. Be sure to check that.
There are single shot ICs that could do this too, but then might not be able to drive an LED.