TOUCH SENSING DEVICE AND TOUCHSCREEN APPARATUS

• US 20150002176A1
• Filed: 09/06/2013
• Published: 01/01/2015
• Est. Priority Date: 06/28/2013
• Status: Abandoned Application

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Kwon, Yong Il, Park, Tah Joon, Jo, Byeong Hak
• Application Number:
  US14/019,694
• Publication Number:
  US 20150002176A1
• Time in Patent Office: Days
• US Class Current: 324/679
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

There are provided a touch sensing device and a touchscreen apparatus. The touch sensing device includes: a node capacitor; a self-capacitor disposed between one terminal of the node capacitor and a ground; a driving circuit applying predetermined driving signals to the node capacitor and the self-capacitor; and a sensing circuit unit integrating electrical charges charged in the node capacitor and the self-capacitor, wherein the driving circuit unit applies predetermined driving signals to the node capacitor and the self-capacitor in different periods.

Claims

1. A touch sensing device comprising:

a node capacitor;

a self-capacitor disposed between one terminal of the node capacitor and a ground;

a driving circuit unit applying predetermined driving signals to the node capacitor and the self-capacitor; and

a sensing circuit unit integrating electrical charges charged in the node capacitor and the self-capacitor,

wherein the driving circuit unit applies the driving signals to the node capacitor and the self-capacitor in different periods.

2. The device of claim 1, wherein the driving circuit unit includes:

a first switch disposed between a supply voltage terminal and the other terminal of the node capacitor;

a second switch disposed between the other terminal of the node capacitor and the ground; and

a third switch disposed between a connection node of the node capacitor and the self-capacitor, and the supply voltage terminal.

3. The device of claim 2, wherein the first and second switches and the third switch operate during different periods.

4. The device of claim 2, wherein the first and second switches operate according to clock signals having a phase difference of 180 degree.

5. The device of claim 1, wherein the sensing circuit unit discharges a portion of an electrical charge charged in the self-capacitor and then integrates the remainder of the charge.

6. The device of claim 2, wherein the sensing circuit unit includes:

an integrating circuit including an operational amplifier having a non-inverted terminal connected to the ground, and a feedback capacitor disposed between an output terminal and an inverted terminal of the operational amplifier;

a fourth switch disposed between the connection node of the node capacitor and the self-capacitor, and the inverted terminal of the operational amplifier;

a fifth switch having one terminal connected to the connection node of the node capacitor and the self-capacitor; and

a current source, wherein the other terminal of the fifth switch is connected to the current source or to the ground, or is floated.

7. The device of claim 1, wherein the node capacitor is formed at an intersection between electrodes of a capacitive type touchscreen panel, and wherein the self-capacitor is formed by the electrodes of the touchscreen panel.

8. A touchscreen apparatus comprising:

a plurality of first electrodes extending in a first axial direction;

a plurality of second electrodes extending in a second axial direction perpendicular to the first axial direction so as to form a plurality of intersections; and

a control unit applying predetermined first driving signals to the plurality of first electrodes to detect changes in mutual-capacitance generated in the plurality of intersections, and applying predetermined second driving signals to the plurality of second electrodes to detect changes in self-capacitance generated in the plurality of second electrodes themselves, wherein the control unit detects changes in the mutual-capacitance and the self-capacitance indifferent periods.

9. The apparatus of claim 8, wherein the control unit includes:

a driving circuit unit applying predetermined driving signals to each of the pluralities of first and second electrodes; and

a sensing circuit unit connected to the plurality of second electrodes, the sensing circuit unit detecting changes in mutual-capacitance generated in a plurality of intersections between the pluralities of first and second electrodes, and detecting changes in self-capacitance generated in the plurality of second electrodes.

10. The apparatus of claim 9, wherein the driving circuit unit applies the driving signals to the pluralities of first and second electrodes during different periods.

11. The apparatus of claim 9, wherein the driving circuit unit applies different driving signals to the pluralities of first and second electrodes.

12. The apparatus of claim 9, wherein the sensing circuit unit integrates the mutual and self capacitance to create an analog signal.

13. The apparatus of claim 12, wherein the sensing circuit unit discharges a portion of the self-capacitance and then integrates the remainder of the capacitance.

14. The apparatus of claim 9, wherein the control unit further includes:

a signal converting unit converting an output signal from the sensing circuit unit into a digital signal; and

a calculating unit determining a touch based on the digital signal.

15. The apparatus of claim 14, wherein the calculation unit determines at least one coordinate of coordinates of the touch, a gesture operation and the number of touch.