Right now my circuit uses a button to pull down a GPIO line of a microcontroller which is pulled up otherwise (see schematic picture). Right now when you press the button the GPIO line drops to 0V and when you release the button it goes back to 3.3V.
What I want to do instead is not have the 0V drop when the button is pressed but 3 seconds after it is pressed. Ideally, I want it to drop and then re-raise back to 3.3V with a <200ms pulse. I drew this as "Ideal Solution" attached picture.
If that's not easy then an acceptable solution is to have the voltage raise back to 3.3v when the button is released as long as it was held for at least 3 seconds. See this voltage diagram as "acceptable solution".
How can I do this with basic components? Or if not basic components, cheap components.
Also note the microcontroller is sleeping during all of this. This is an external wakeup circuit, so I can't use the microcontroller in any way to solve this problem.
What I want to do instead is not have the 0V drop when the button is pressed but 3 seconds after it is pressed. Ideally, I want it to drop and then re-raise back to 3.3V with a <200ms pulse. I drew this as "Ideal Solution" attached picture.
If that's not easy then an acceptable solution is to have the voltage raise back to 3.3v when the button is released as long as it was held for at least 3 seconds. See this voltage diagram as "acceptable solution".
How can I do this with basic components? Or if not basic components, cheap components.
Also note the microcontroller is sleeping during all of this. This is an external wakeup circuit, so I can't use the microcontroller in any way to solve this problem.
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