The TTP223 capacitive touch module detects the change in capacitance caused by a finger touching or approaching the sensor pad. It outputs a clean digital HIGH signal without requiring physical pressure.
| IC | TTP223-BA6 |
| Supply voltage | 2.0 – 5.5 V |
| Response time | 60 ms (typical) |
| Output | Digital active-HIGH |
| Sensitivity | Adjustable via pads |
| Package | SMD module |
A relaxation oscillator measures the capacitance of the touch pad electrode. When a finger (which has ~100 pF body capacitance) comes within range, the oscillator frequency changes. Internal comparator logic outputs a HIGH when threshold is exceeded.
Affected by moisture, condensation, and nearby metal. False triggers possible through thin materials. Cannot track multi-touch or position. Requires re-calibration if environment changes significantly.