发明名称 METHODS AND SYSTEMS FOR DETECTING A CAPACITANCE USING SIGMA-DELTA MEASUREMENT TECHNIQUES
摘要 Methods, systems and devices are described for detecting a measurable capacitance using sigma-delta measurement techniques. According to various embodiments, a voltage is applied to the measurable capacitance using a first switch. The measurable capacitance is allowed to share charge with a passive network. If the charge on the passive network is past a threshold value, then the charge on the passive network is changed by a known amount for a sufficient number of repetitions until the measurable capacitance can be detected. Such a detection scheme may be readily implemented using conventional components, and can be particularly useful in sensing the position of a finger, stylus or other object with respect to a button, slider, touchpad or other input sensor.
申请公布号 US2009039902(A1) 申请公布日期 2009.02.12
申请号 US20080252150 申请日期 2008.10.15
申请人 SYNAPTICS INCORPORATED 发明人 HARGREAVES KIRK;REYNOLDS JOSEPH KURTH;ELY DAVID;HAINES JULIAN
分类号 G01R27/26 主分类号 G01R27/26
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