I'm doing a reverse engineering research about the PlayStation 4 controller. I want to know how do the analog buttons work (the triggers in the bottom, not the analog sticks). I've found a nice teardown album and, there, I've seen this image:
I know from this page that the flexible film pins for each analog trigger are these:
- Common: Oscillating between 0 and 3.3V.
- Sig: Voltage divider output, active low.
I want to know if it is:
- A capacitive sensor.
- A piezoelectric film.
- A force-sensitive resistor
And, by the way, how does the circuit attached work? I suppose it will have some kind of Analog Digital Converter, filtering, amplification...