I'm using some Schmitt-trigger inputs for debouncing the interrupt problems.
Referring to above circuit, the circuit has a RC circuit and the output of the RC circuit goes to the Schmitt-trigger IC(74HC14). Also, I soldered like this circuit and the look is like as below picture.
Well, the picture is not good I apologize for the view. (18k : R1, 2k : R2, 0.1u : C1)
Anyway, I'm convinced of the equality of the circuit picture and the real one. However there is a very small issue.
The output of the Schmitt-trigger IC is connected to the MCU interrupt pin. So, if the Schmitt-trigger output goes to low(I use falling-edge-triggered interrupt), the MCU will run some ISR. Suppose I "bring(NOT push the button)" my hand to control the device on my own. At most, the device not malfunction. However, very occasionally the device goes to interrupt mode(ISR).
The schmitt-trigger goes to MCU(ATmega2560, STM32F411RE, and so forth) and the MCU has some attached interrupts that can respond for the some schmitt-trigger inputs. And if the problem occurs, MCU just execute some ISRs. I thought the problem is occurred by the ESD so I used some TVSs and collected all the GNDs as near as the SMPS input, but the issue is not entirely solved. The problem hardly happens(probably just one time of a day) so this wouldn't be important one, but what could be the cause of this situation? Could I get some intuitions for the issue and the solutions?