发明名称 |
Method and apparatus for improving dynamic range of a touchscreen controller |
摘要 |
A touchscreen system for increasing the dynamic range of the system comprising a touchscreen coupled to an offset cancellation element and a capacitance measuring element. The offset cancellation element is configured to be dynamically changed in capacitance such that it offsets parasitic and sensor capacitances of the touchscreen sensors thereby leaving only touch event capacitance to be measured by the measuring element. The offset cancellation element is able to adjust to the initial unwanted capacitances of each sensor as well as dynamically adjust to changes in the unwanted capacitance due to the environment. In some embodiments, the offset cancellation element is a capacitance digital-to-analog converter that is controlled by a controller for offsetting the unwanted capacitance. As a result, the touchscreen system is able to utilize a small integrating capacitor thereby lowering cost and improving the dynamic range of the system. |
申请公布号 |
US8599167(B2) |
申请公布日期 |
2013.12.03 |
申请号 |
US20110986776 |
申请日期 |
2011.01.07 |
申请人 |
JOHARAPURKAR ASHUTOSH RAVINDRA;CHAN PATRICK;MAXIM INTEGRATED PRODUCTS, INC. |
发明人 |
JOHARAPURKAR ASHUTOSH RAVINDRA;CHAN PATRICK |
分类号 |
G06F3/045 |
主分类号 |
G06F3/045 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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