Liquid detecting method and controller for a capacitive touch pad

A liquid detecting method for a capacitive touch pad, wherein the capacitive touch pad comprises multiple first electrodes and multiple second electrodes, multiple sensing points are formed at intersections of the multiple first electrodes and the multiple second electrodes;

• the method comprising steps of:
• performing a first mutual capacitance measurement of the multiple sensing points, which comprises sensing each of the multiple sensing points for a first period of time to obtain a first sensing value of each of the multiple sensing points;
• performing a second mutual capacitance measurement of the multiple sensing points, which comprises sensing each of the multiple sensing points for a second period of time to obtain a second sensing value of each of the multiple sensing points, wherein the second period of time is less than the first period of time;
• and
• determining whether there is liquid on the capacitive touch pad according to the multiple first sensing values and the multiple second sensing values.

A controller for detecting whether there is liquid on a capacitive touch pad, wherein the capacitive touch pad comprises multiple first electrodes and multiple second electrodes, and multiple sensing points are formed at intersections of the multiple first electrodes and the multiple second electrodes;

• the controller comprising of:
• a storage media storing a firmware program;
• a processor coupled to the storage media and executing the firmware program to perform steps of:
• performing a first mutual capacitance measurement of the multiple sensing points with a first driving signal having a first frequency to obtain a first sensing value of each of the multiple sensing points;
• performing a second mutual capacitance measurement of the multiple sensing points with a second driving signal having a second frequency to obtain a second sensing value of each of the multiple sensing points, the second frequency being higher than the first frequency;
• and
• determining whether there is liquid on the capacitive touch pad according to the multiple first sensing values and the multiple second sensing values.

A controller for detecting whether there is liquid on a capacitive touch pad, wherein the capacitive touch pad comprises multiple first electrodes and multiple second electrodes, and multiple sensing points are formed at intersections of the multiple first electrodes and the multiple second electrodes;

• the controller comprising of:
• a storage media storing a firmware program;
• a processor coupled to the storage media and executing the firmware program to perform steps of:
• performing a first mutual capacitance measurement of the multiple sensing points, which comprises sensing each of the multiple sensing points for a first period of time to obtain a first sensing value of each of the multiple sensing points respectively;
• performing a second mutual capacitance measurement of the multiple sensing points, which comprises sensing each of the multiple sensing points for a second period of time to obtain a second sensing value of each of the multiple sensing points, wherein the second period of time is less than the first period of time;
• and
• determining whether there is liquid on the capacitive touch pad according to the multiple first sensing values and the multiple second sensing values.