It's a Digital Sensor TTP223B Module Capacitive Touch Switch. The Digital Sensor TTP223B Module Capacitive Touch Switch is based on a touch-sensing IC (TTP223B) capacitive touch switch module. When a touch is sensed on the circular marked region, it outputs high and switches to the quick response state. When not being touched for 12 seconds, it switches to low power state again. In addition to the thin paper (non-metallic) covering the surface of the module, as long as the correct location of the touch, you can make hidden in the walls, desktops and other parts of buttons.
|Response time (touch mode)||60ms|
|Response time (low power mode)||220ms|