Capacitor discharge circuit

[Faizan]

Hi!

I have interface external piezo element with my ARM controller to get the piezo data. But after sometime my controller is off. I didn't getting why this problem happens. As per my knowledge piezo work as a capacitor and it will generate the voltage, So may be due to generate high voltage this problem happens. My piezo has generate voltage in mili volt. Can i use as capacitor in series to solve this problem ?

[MartinBL]

There are literally thousands of reason why a controller might shut down.

1. You need to debug your code to see if there might be something in your firmware that doesn't work.
2. Maybe you can remove your piezo sensor and see if that helps. If it does you should start looking at voltages etc.
3. How long does it take before the controller shuts down?
4. Is the controller or piezo doing anything special when it shuts down?

[Faizan]

I am taking two data simultaneously which is  Gyro an piezo  data.

I have one more question piezo element is convert mechanical energy to electrical energy so it has to generate energy or voltage as output. In my case i have  directly connected piezo with ARM cortex gpio pin. So my question is generated energy or voltage throw piezo is goes into controller or somewhere else ? 

[MartinBL]

Yes, an overvoltage could potentially damage your controller. A few solutions are discussed here: Piezoelectric Sensor and the ADC.