TOUCH INPUT DEVICE AND TOUCH SENSOR CIRCUIT

• US 20100321336A1
• Filed: 06/17/2010
• Published: 12/23/2010
• Est. Priority Date: 06/18/2009
• Status: Active Grant

• Current Assignee: Raydium Semiconductor Corporation
• Original Assignee: Raydium Semiconductor Corporation
• Inventors: CHOU, Shih-Tzung, Kuang, Yu, Rao, Yong-Nien, Wu, Zong-Lin
• Granted Patent: US 8,736,572 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• 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

The invention discloses a touch input device and a touch sensor circuit. The touch input device includes a touch panel, a selection module and a differential detection module. The touch panel includes a plurality of capacitive nodes thereon. The selection module is electrically connected with the capacitive nodes of the touch panel. The selection module selects a first capacitive node and a second capacitive node from the capacitive nodes. The second capacitive node is close to the first capacitive node. The differential detection module, electrically connected to the selection module, is used for detecting a capacitance difference between the first capacitive node and the second capacitive node. According to the capacitance difference, the differential detection module generates a touch detection signal.

Claims

1. A touch input device, comprising:

a touch panel comprising;

a plurality of capacitive nodes formed and spread on the touch panel;

a selection module electrically connected with the capacitive nodes of the touch panel, the selection module selecting a first capacitive node and a second capacitive node from the capacitive nodes, the second capacitive node being adjacent to the first capacitive node; and

a differential detection module electrically connected with the selection module, the different detection module detecting a capacitance difference between the first capacitive node and the second capacitive node selected by the selection module, so as to generate a touch detection signal.

2. The touch input device of claim 1, wherein the touch panel is a projected capacitive touch panel.

3. The touch input device of claim 1, wherein the touch panel comprises a plurality of X-directional conductive lines and a plurality of Y-directional conductive lines, the X-directional conductive lines and the Y-directional conductive lines are arranged in a grid shape, and each of the capacitive nodes is formed corresponding to one of the X-directional conductive lines and one of the Y-directional conductive lines.

4. The touch input device of claim 3, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select one X-directional conductive line from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select the first capacitive node; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select one X-directional conductive line from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select the second capacitive node.

5. A touch input device, comprising:

a touch panel comprising;

a plurality of capacitive nodes formed and spread on the touch panel;

a selection module electrically connected with the capacitive nodes of the touch panel, the selection module selecting some capacitive nodes from the plurality of capacitive nodes to form a first capacitive node set and selecting some capacitive nodes from the plurality of capacitive nodes to form a second capacitive node set, the capacitive nodes of the second capacitive node set being adjacent to the capacitive nodes of the first capacitive node set; and

a differential detection module electrically connected with the selection module, the different detection module detecting a total capacitance difference between the first capacitive node set and the second capacitive node set selected by the selection module, so as to generate a touch detection signal.

6. The touch input device of claim 5, wherein the touch panel is a projected capacitive touch panel.

7. The touch input device of claim 5, wherein the touch panel comprises a plurality of X-directional conductive lines and a plurality of Y-directional conductive lines, the X-directional conductive lines and the Y-directional conductive lines are arranged in a grid shape, and each of the capacitive nodes is formed corresponding to one of the X-directional conductive lines and one of the Y-directional conductive lines.

8. The touch input device of claim 7, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select one X-directional conductive line from the X-directional conductive lines and select at least two Y-directional conductive lines from the Y-directional conductive lines, so as to select and form the first capacitive node set; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select one X-directional conductive line from the X-directional conductive lines and select at least two Y-directional conductive lines from the Y-directional conductive lines, so as to select and form the second capacitive node set.

9. The touch input device of claim 7, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select at least two X-directional conductive lines from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select and form the first capacitive node set; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select at least two X-directional conductive lines from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select and form the second capacitive node set.

10. The touch input device of claim 7, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select at least two X-directional conductive lines from the X-directional conductive lines and select at least two Y-directional conductive lines from the Y-directional conductive lines, so as to select and form the first capacitive node set; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select at least two X-directional conductive lines from the X-directional conductive lines and select at least two Y-directional conductive lines from the Y-directional conductive lines, so as to select and form the second capacitive node set.

11. The touch input device of claim 7, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select a first X-directional conductive line from the X-directional conductive lines and make the Y-directional conductive lines grounded or floating, so as to select all capacitive nodes corresponding to the first X-directional conductive line and form the first capacitive node set; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select a first X-directional conductive line from the X-directional conductive lines and make the Y-directional conductive lines grounded or floating, so as to select all capacitive nodes corresponding to the second X-directional conductive line and form the second capacitive node set.

12. The touch input device of claim 7, wherein the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select a first Y-directional conductive line from the Y-directional conductive lines and make the X-directional conductive lines grounded or floating, so as to select all capacitive nodes corresponding to the first Y-directional conductive line and form the first capacitive node set; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select a first Y-directional conductive line from the Y-directional conductive lines and make the X-directional conductive lines grounded or floating, so as to select all capacitive nodes corresponding to the second Y-directional conductive line and form the second capacitive node set.

13. The touch input device of claim 5, wherein when the differential detection module detects the total capacitance difference between the first capacitive node set and the second capacitive node set, the selection module further selects a first capacitive node and a second capacitive node from the capacitive nodes of the first capacitive node set, and the differential detection module further detects a capacitance difference between the first capacitive node and the second capacitive node, so as to generate the touch detection signal.

14. A touch sensor circuit, suitable for a touch panel, a plurality of capacitive nodes being formed and spread on the touch panel, the touch sensor circuit comprising:

a selection module electrically connected with the capacitive nodes of the touch panel, the selection module selecting a first capacitive node and a second capacitive node from the capacitive nodes, the second capacitive node being adjacent to the first capacitive node; and

a differential detection module electrically connected with the selection module, the different detection module detecting a capacitance difference between the first capacitive node and the second capacitive node selected by the selection module, so as to generate a touch detection signal.

15. The touch sensor circuit of claim 14, wherein the touch panel comprises a plurality of X-directional conductive lines and a plurality of Y-directional conductive lines, and the selection module comprises:

a first multiplexer coupled between the touch panel and the differential detection module, the first multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the first multiplexer to select one X-directional conductive line from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select the first capacitive node; and

a second multiplexer coupled between the touch panel and the differential detection module, the second multiplexer being electrically connected with the X-directional conductive lines and the Y-directional conductive lines, the selection module utilizing the second multiplexer to select one X-directional conductive line from the X-directional conductive lines and select one Y-directional conductive line from the Y-directional conductive lines, so as to select the second capacitive node.