The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 07, 2021
Filed:
Mar. 07, 2018
Knowles Electronics, Llc, Itasca, IL (US);
Colin Steele, Edinburgh, GB;
Rene Scheuner, Winterthur, CH;
Thomas Christen, Zürich, CH;
Mark Niederberger, Einsiedeln, CH;
Knowles Electronics, LLC, Itasca, IL (US);
Abstract
An arrangement () to calibrate a capacitive sensor interface () includes a capacitive sensor () having a capacitance (cmem, cmemsp, cmemsm) and a charge storing circuit () having a changeable capacitance (cdum, cdump, cdumm). A test circuit () applies a test signal (vtst) to the capacitive sensor () and the charge storing circuit (). An amplifier circuit () has a first input connection (E) coupled to the capacitive sensor () and a second input connection (E) coupled to the charge storing circuit (). The amplifier circuit () provides an output signal (Vout) in dependence on a first input signal (ΔVerr) applied to the first input connection (E) and a second input signal (ΔVerr) applied to the second input connection (E). A control circuit () is configured to trim the capacitance (cdum, cdump, cdumm) of the charge storing circuit () such that the level of the output signal (Vout) tends to the level of zero.