Invention Grant
- Patent Title: Sensing circuit and method for a capacitive touch panel
- Patent Title (中): 电容式触摸屏的感应电路和方法
-
Application No.: US12652260Application Date: 2010-01-05
-
Publication No.: US08593429B2Publication Date: 2013-11-26
- Inventor: Tsun-Min Wang , Chun-Yu Lin , Te-Sheng Chiu , Chun-Chung Huang
- Applicant: Tsun-Min Wang , Chun-Yu Lin , Te-Sheng Chiu , Chun-Chung Huang
- Applicant Address: TW Hsinchu
- Assignee: Elan Microelectronics Corporation
- Current Assignee: Elan Microelectronics Corporation
- Current Assignee Address: TW Hsinchu
- Agency: Muncy, Geissler, Olds & Lowe, PLLC
- Priority: TW98100727A 20090109; TW98117362A 20090525
- Main IPC: G06F3/045
- IPC: G06F3/045

Abstract:
A sensing method and circuit for a capacitive touch panel sense the capacitance variation of a lateral capacitor formed at the intersection of two traces of the capacitive touch panel, to distinguish a real point from a ghost point. A sensing cycle includes two non-overlapping clock phases. In the first clock phase, the voltages across the lateral capacitor and across a sensing capacitor are set. In the second clock phase, the voltage at a first terminal of the lateral capacitor is changed, and a second terminal of the lateral capacitor is connected to a first terminal of the sensing capacitor, causing a voltage variation at a second terminal of the sensing capacitor. This voltage variation is used to determine whether the intersection is touched. The sensing method and circuit reflect the status of the lateral capacitor in real-time and prevent the location of the touch point from being misjudged.
Public/Granted literature
- US20100177059A1 SENSING CIRCUIT AND METHOD FOR A CAPACITIVE TOUCH PANEL Public/Granted day:2010-07-15
Information query