AN2843 introduces the features and applications of the 12-channel capacitive touchkey controller STMPE1208S.
The document introduces the STEVAL-IHI002V1, a demonstration board designed to replace conventional mechanical keyboards using the STMPE1208S. This device is a 12-bit GPIO expander with 12-channel capacitive sensors that interfaces with a main MCU via an I2C bus. It supports various input types including a wheel, a slider, and five buttons.
| GPIO Bits | 12-bit |
|---|---|
| Sensor Channels | 12-channel |
| Interrupt Types | General and Touch |
It is a 12-bit GPIO device with additional 12-channel capacitive sensors.
It detects finger contact through the additional capacitance introduced to the sensor.
It ensures consistent key sensitivity even when environmental factors like temperature and humidity change.