Invention Grant
- Patent Title: Coded integration of a self-capacitance array
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Application No.: US14286949Application Date: 2014-05-23
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Publication No.: US10558302B2Publication Date: 2020-02-11
- Inventor: Shahrooz Shahparnia , Marduke Yousefpor
- Applicant: Apple Inc.
- Applicant Address: US CA Cupertino
- Assignee: Apple Inc.
- Current Assignee: Apple Inc.
- Current Assignee Address: US CA Cupertino
- Agency: Kubota & Basol LLP
- Main IPC: G06F3/044
- IPC: G06F3/044

Abstract:
Coded integration of a self-capacitance array to improve signal-to-noise ratio (SNR) of self-capacitance measurements is disclosed. A composite measurement of the self-capacitance of a plurality of electrodes can be measured for a plurality of integration periods. The composite measurements can include weighted contributions of charge from the plurality of electrodes, the weighting corresponding to a code. In some examples, the weighted contribution can include positive contributions integrated by a first integrator circuit and negative contributions integrated by a second integrator circuit. The composite measurements of the self-capacitance for the plurality of integration periods can be decoded to extract the self-capacitance measurement for the electrodes. The SNR for the self-capacitance measurements can therefore be improved by increasing the number of samples during the total integration period without requiring dedicated sensing circuitry for the electrodes.
Public/Granted literature
- US20150338952A1 CODED INTEGRATION OF A SELF-CAPACITANCE ARRAY Public/Granted day:2015-11-26
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