Ideas / Alternate solutions to trigger a switch

Question

Thank you for reading my question, I hope to learn a new way to solve my problem. I don't expect anyone to design a cicuit etc as hopefully I can do that myself, just some pointers at possible components to consider.

I have a device that has a built in electronic timer, after a while an LED lights up and I have to press a button to continue using the device.

The button is just a normally open contact switch.

My first thought is to use an arduino and either directly from the LED or via an opto-isolator monitor the LED, when it lights up use the arduino to momentarily close the switch thus resetting the internal timer.

The circuit board itself has regulated 12v and 5v available but since it is mains powered I can power from pretty much anything.

Perhaps there are some other IC's or transistor etc I could use on some bread-board to trigger the switch instead of having an arduino.

I'm not very familiar with how to do this so any pointers at what to look at would be greatly appreciated.

Many thanks.

Answer 1

You could always have the output for LED go through an RC delay and an XOR gate.
You can then use this output signal and feed it directly to where the button is fitted as it would simulate a button press of 'x' amount of time.

^{simulate this circuit – Schematic created using CircuitLab}

I've also done a simulation to show you what the effects would be, for a longer/shorter pulse duration you would need to play around with the value of the resistor and capacitor but only there is lots of help for RC calculations, google "RC Calculator"

Simulation Link