Patent ID: 11966531
Assignee: REALTEK SEMICONDUCTOR CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 12:
13. A capacitive sensing method, comprising:
transmitting a first reference voltage to a first input terminal of an amplifier circuit and coupling a second input terminal of the amplifier circuit to an output terminal the amplifier circuit during a first phase, wherein the second input terminal is coupled to the output terminal via a switch circuitry and is coupled to ground via a capacitor under-test;
transmitting a second reference voltage to the first input terminal during a second phase;
adjusting an output voltage of the output terminal and generating a control signal according to the output voltage and the second reference voltage during a third phase; and
starting counting when entering the third phase and stopping counting according to the control signal to generate a count value, wherein the count value indicates a capacitance value change of the capacitor under-test.