Invention Grant
- Patent Title: Capacitive sensor system with noise reduction
- Patent Title (中): 具有降噪功能的电容传感器系统
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Application No.: US12895087Application Date: 2010-09-30
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Publication No.: US08941394B2Publication Date: 2015-01-27
- Inventor: Bradley Martin , Dazhi Wei
- Applicant: Bradley Martin , Dazhi Wei
- Applicant Address: US TX Austin
- Assignee: Silicon Laboratories Inc.
- Current Assignee: Silicon Laboratories Inc.
- Current Assignee Address: US TX Austin
- Main IPC: G01R27/26
- IPC: G01R27/26 ; G06F3/044 ; G06F3/041

Abstract:
A system for reducing noise when detecting the capacitance value of a capacitor in a touch display that operates in a potentially noisy environment. A capacitance sensor is provided for determining the size of the capacitor in the touch screen display and includes a charging circuit that charges the capacitor and a discharge circuit that resets the charge of the capacitor to substantially zero. A control circuit controls the capacitance sensor and the operation of the charge and discharge circuits in accordance with a predetermined charging/discharging algorithm to resolve the value of the capacitor and output such value in a sampling operation. The operation of the control circuit and the charging/discharging algorithm is subject to errors as a function of the noisy environment, which errors will be reflected in the output value. A noise reduction circuit is provided to modify the operation of the control circuit to reduce noise.
Public/Granted literature
- US20110157077A1 CAPACITIVE SENSOR SYSTEM WITH NOISE REDUCTION Public/Granted day:2011-06-30
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