TOUCH INPUT DEVICE FOR SWITCHING DRIVING SIGNALS

• US 20130033441A1
• Filed: 05/10/2012
• Published: 02/07/2013
• Est. Priority Date: 08/03/2011
• Status: Active Grant

• Current Assignee: Raydium Semiconductor Corporation
• Original Assignee: Raydium Semiconductor Corporation
• Inventors: LIU, KAI MING, CHOU, SHIH TZUNG, LU, YA LING
• Granted Patent: US 8,743,085 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• 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

A touch input device for switching driving signals includes a touch panel and a panel driving circuit for driving the touch panel. The panel driving circuit includes a selecting circuit, a driving signal generating circuit, and a touch sensing circuit. The driving signal generating circuit transmits a driving signal to the touch panel. The selecting circuit includes a multiplexer, which controls sensing lines that do not comprise either an X directional measuring channel or a Y directional measuring channel to be grounded or floating in accordance with the driving signal.

Claims

1. A touch input device for switching driving signals, the touch input device comprising:

a touch panel, including;

a plurality of X-directional sensing lines;

a plurality of Y-directional sensing lines, wherein the X-directional sensing lines and the Y-directional sensing lines are arranged in a staggered manner; and

a plurality of mutual capacitors formed between every X-directional sensing line and every Y-directional sensing line; and

a panel driving circuit, configured for driving the touch panel, the panel driving circuit comprising;

a selecting circuit including a multiplexer, wherein the selecting circuit selects and shifts an X-directional measuring channel or a Y-directional measuring channel in accordance with a predetermined number of the X-directional sensing lines and Y-directional sensing lines;

a driving signal generating circuit configured for transmitting a driving signal to the X-directional measuring channel or the Y-directional measuring channel in accordance with a clock signal, wherein the multiplexer controls the X-directional sensing lines and Y-directional sensing lines that do not comprise either the X-directional measuring channel or the Y-directional measuring channel to be grounded or floating in accordance with the driving signal; and

a touch sensing circuit configured to detect two voltages of the Y-directional sensing lines in the Y-directional measuring channel.

2. The touch input device according to claim 1, wherein the X-directional sensing lines and the Y-directional sensing lines that do not comprise the X-directional measuring channel or the Y-directional measuring channel are floating.

3. The touch input device according to claim 1, wherein the X-directional sensing lines and the Y-directional sensing lines that do not comprise the X-directional measuring channel or the Y-directional measuring channel are grounded.

4. The touch input device according to claim 1, wherein when two Y-directional sensing lines, adjacent to the Y-directional measuring channel, are grounded, the other Y-directional sensing lines and the X-directional sensing lines that do not comprise the X-directional measuring channel are floating.

5. The touch input device according to claim 1, wherein when two X-directional sensing lines adjacent to the X-directional measuring channel and two Y-directional sensing lines adjacent to the Y-directional measuring channel are grounded, the other Y-directional sensing lines and the other X-directional sensing lines are floating.

6. The touch input device according to claim 1, wherein when the X-directional sensing lines that do not comprise the X-directional measuring channel and two Y-directional sensing lines adjacent to the Y-directional measuring channel are grounded, then the other Y-directional sensing lines are floating.

7. The touch input device according to claim 1, wherein when the Y-directional sensing lines that do not comprise the Y-directional measuring channel are grounded, then the X-directional sensing lines that do not comprise the X-directional measuring channel are floating.

8. The touch input device according to claim 1, wherein when two X-directional sensing lines adjacent to the X-directional measuring channel and the Y-directional sensing lines that do not comprise the Y-directional measuring channel are grounded, then the other X-directional sensing lines are floating.

9. The touch input device according to claim 1, wherein when two X-directional sensing lines adjacent to the X-directional measuring channel are grounded, then the other X-directional sensing lines and the Y-directional sensing lines that do not comprise the Y-directional measuring channel are floating.

10. The touch input device according to claim 1, wherein when the X-directional sensing lines that do not comprise the X-directional measuring channel are grounded, then the Y-directional sensing lines that do not comprise the Y-directional measuring channel are floating.

11. The touch input device according to claim 1, further comprising a determining circuit configured for judging a touch position in accordance with the two voltages detected by the touch sensing circuit.