8.4.2.2 Active Key Scan Mode

When the TCA8418 is in idle key scan mode, the device awaits a key press. Once a key is pressed in the array, a low signal on one of the ROW pin inputs triggers an interrupt, which will turn on the internal oscillator and enter the active key scan mode. At this point, the TCA8418 will start the key scan algorithm to determine which key is being pressed, and/or it will use the internal oscillator for debouncing. Once all keys have been released, the device will enter idle key scan mode.