Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Reexamination Certificate
2007-10-30
2008-11-18
Nguyen, Vincent Q (Department: 2831)
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
Reexamination Certificate
active
07453270
ABSTRACT:
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.
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Ely David
Haines Julian
Hargreaves Kirk
Reynolds Joseph Kurth
Ingrassia Fisher & Lorenz P.C.
Nguyen Vincent Q
Synaptics Incorporated
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