Touch sensing device and electronic apparatus having malfunction prevention function
A touch sensing device applied to an electronic device including a side portion having a cover that is nonconductive, and a frame that is conductive, includes: a first touch sensing portion including a first sensing electrode and a first sensing inductor disposed inside the cover and electrically connected to each other, wherein, in response to a touch applied through the cover by a human body, a capacitance is varied by the first touch sensing portion according to parasitic capacitance generated between the first sensing electrode and the human body according to the touch applied through the cover; and a reference sensing portion including a reference coil disposed inside the side portion and configured to provide reference inductance of the reference coil that is constant, regardless of a touch applied through the frame.
1. A touch sensing device applied to an electronic device including a side portion having a cover that is nonconductive, and a frame that is conductive, the touch sensing device comprising:
a first touch sensing portion comprising a first sensing electrode and a first sensing inductor disposed inside the cover and electrically connected to each other, wherein, in response to a touch applied through the cover by a human body, a capacitance is varied by the first touch sensing portion according to parasitic capacitance generated between the first sensing electrode and the human body according to the touch applied through the cover; and
a reference sensing portion comprising a reference coil disposed inside the side portion and configured to provide reference inductance of the reference coil that is constant, regardless of a touch applied through the frame.
2. The touch sensing device of claim 1 , wherein the reference sensing portion further comprises a shielding member disposed between the reference coil and the side portion, and configured to block external influences.
3. The touch sensing device of claim 2 , wherein the shielding member is any one of a shield-can, a magnetic sheet, and an electromagnetic wave absorber.
4. The touch sensing device of claim 1 , wherein the first sensing electrode is disposed inside a first touch member, and the first touch member is a part of the cover,
wherein the first sensing inductor is electrically connected to the first sensing electrode and is mounted on a substrate, and
wherein the first touch sensing portion further comprises a first connection lead electrically connecting the first sensing electrode to one end of the first sensing inductor.
5. The touch sensing device of claim 1 , further comprising:
a second touch sensing portion comprising a second sensing electrode and a second sensing inductor disposed inside the cover, and electrically connected to each other,
wherein, in response to another touch applied through the cover by the human body, capacitance is varied by the second touch sensing portion according to parasitic capacitance generated between the second sensing electrode and the human body according to the other touch applied through the cover.
6. The touch sensing device of claim 5 , wherein the second sensing electrode is disposed inside a second touch member that is a part of the cover,
wherein the second sensing inductor is electrically connected to the second sensing electrode and is mounted on a substrate, and
wherein the second touch sensing portion further comprises a second connection lead electrically connecting the second sensing electrode to one end of the second sensing inductor.
7. The touch sensing device of claim 6 , wherein the reference coil, the first sensing inductor, and the second sensing inductor have same characteristics.
8. The touch sensing device of claim 5 , further comprising a circuit portion configured to:
generate a first touch detection signal and a second touch detection signal based on the capacitance varied by the first touch sensing portion and the capacitance varied by the second touch sensing portion;
generate a reference signal based on reference inductance; and
detect whether each of the touch and the other touch occurs, based on the reference signal, and the first touch detection signal, and the second touch detection signal.
9. An electronic device, comprising:
a side portion having a cover that is nonconductive and a frame that is conductive;
a touch switch portion comprising a first touch member that is a part of the cover;
a first touch sensing portion comprising a first sensing electrode and a first sensing inductor disposed inside the cover and electrically connected to each other, wherein, in response to a touch applied through the first touch member by a human body, capacitance is varied by the first touch sensing portion according to parasitic capacitance generated between the first sensing electrode and the human body according to the touch applied through the first touch member; and
a reference sensing portion comprising a reference coil disposed inside the side portion and configured to provide reference inductance of the reference coil that is constant, regardless of a touch applied through the frame.
10. The electronic device of claim 9 , wherein the reference sensing portion further comprises a shielding member disposed between the reference coil and the side portion, and configured to block external influences.
11. The electronic device of claim 10 , wherein the first sensing electrode is disposed inside the first touch member;
wherein the first sensing inductor is electrically connected to the first sensing electrode, and mounted on a substrate; and
wherein the first sensing portion further comprises a first connection lead electrically connecting the first sensing electrode to one end of the first sensing inductor.
12. The electronic device of claim 10 , further comprising:
a second touch sensing portion comprising a second sensing electrode and a second sensing inductor disposed inside the cover and electrically connected to each other,
wherein, in response to a touch applied through the cover by the human body, capacitance is varied by the second touch sensing portion according to parasitic capacitance generated between the second sensing electrode and the human body according to the touch applied through the cover.
13. The electronic device of claim 12 , wherein the second sensing electrode is disposed inside a second touch member that is a part of the cover,
wherein the second sensing inductor is electrically connected to the second sensing electrode and mounted on a substrate, and
wherein the second touch sensing portion further comprises a second connection lead electrically connecting the second sensing electrode to one end of the second sensing inductor.
14. The electronic device of claim 13 , wherein the reference coil, the first sensing inductor, and the second sensing inductor have same characteristics.
15. The electronic device of claim 14 , further comprising a circuit portion configured to:
generate first and second touch detection signals based on the capacitance varied by the first touch sensing portion and the capacitance varied by the second touch sensing portion;
generate a reference signal based on the reference inductance; and
detect whether each of the touch applied through the first touch member and the touch applied through the cover occurs, based on the reference signal, the first sensing signal, and the second sensing signal.
16. The electronic device of claim 10 , wherein the shielding member is any one of a shield-can, a magnetic sheet, and an electromagnetic wave absorber.