TOUCH SENSING SYSTEM, CAPACITANCE SENSING APPARATUS AND CAPACITANCE SENSING METHOD THEREOF
First Claim
1. A capacitance sensing apparatus comprising:
- a plurality of switch units, each of the switch units having a first end, a second end, and a third end, the third end of each of the switch units being coupled to a corresponding sensing capacitor; and
a differential sensing circuit having a sensing input end, a reference input end, and an output end, the sensing input end being coupled to the first end of each of the switch units to receive a capacitance under test provided by at least one of the sensing capacitors, the reference input end being coupled to the second end of each of the switch units to receive a reference capacitance provided by at least one of the sensing capacitors,wherein the differential sensing circuit compares the capacitance under test and the reference capacitance to output a first difference between the capacitance under test and the reference capacitance through the output end of the differential sensing circuit.
1 Assignment
0 Petitions
Accused Products
Abstract
A touch sensing system includes a touch input interface and at least one capacitance sensing apparatus. The capacitance sensing apparatus includes a plurality of switch units and a differential sensing circuit. Each of the switch units is coupled to a corresponding sensing capacitor. A sensing input end of the differential sensing circuit receives a capacitance under test provided by at least one of the sensing capacitors. A reference input end of the differential sensing circuit receives a reference capacitance provided by at least one of the sensing capacitors. The differential sensing circuit compares the capacitance under test and the reference capacitance to output a first difference between the capacitance under test and the reference capacitance through an output end of the differential sensing circuit. A capacitance sensing method is also provided.
-
Citations
30 Claims
-
1. A capacitance sensing apparatus comprising:
-
a plurality of switch units, each of the switch units having a first end, a second end, and a third end, the third end of each of the switch units being coupled to a corresponding sensing capacitor; and a differential sensing circuit having a sensing input end, a reference input end, and an output end, the sensing input end being coupled to the first end of each of the switch units to receive a capacitance under test provided by at least one of the sensing capacitors, the reference input end being coupled to the second end of each of the switch units to receive a reference capacitance provided by at least one of the sensing capacitors, wherein the differential sensing circuit compares the capacitance under test and the reference capacitance to output a first difference between the capacitance under test and the reference capacitance through the output end of the differential sensing circuit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A touch sensing system comprising:
-
a touch input interface comprising a plurality of sensing capacitors; and at least one capacitance sensing apparatus comprising; a plurality of switch units, each of the switch units having a first end, a second end, and a third end, the third end of each of the switch units being coupled to a corresponding one of the sensing capacitors; and a differential sensing circuit having a sensing input end, a reference input end, and an output end, the sensing input end being coupled to the first end of each of the switch units to receive a capacitance under test provided by at least one of the sensing capacitors, the reference input end being coupled to the second end of each of the switch units to receive a reference capacitance provided by at least one of the sensing capacitors, wherein the differential sensing circuit compares the capacitance under test and the reference capacitance to output a first difference between the capacitance under test and the reference capacitance through the output end of the differential sensing circuit. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. A capacitance sensing method comprising:
-
providing a plurality of switch units and a differential sensing circuit, wherein each of the switch units is coupled to a corresponding sensing capacitor; receiving a capacitance under test provided by at least one of the sensing capacitors; receiving a reference capacitance provided by at least one of the sensing capacitors; and comparing the capacitance under test and the reference capacitance to obtain a first difference between the capacitance under test and the reference capacitance. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29, 30)
-
Specification