CPC G01V 3/088 (2013.01) [B60L 53/122 (2019.02); B60L 53/124 (2019.02); B60L 53/38 (2019.02); B60L 53/65 (2019.02); G01V 3/101 (2013.01); G06F 18/217 (2023.01); H02J 50/10 (2016.02); H02J 50/60 (2016.02); H02J 50/90 (2016.02); H05B 1/0288 (2013.01); G06V 2201/08 (2022.01)] | 14 Claims |
1. A detection circuit comprising:
a plurality of capacitive sense elements configured for living object detection;
a measurement circuit electrically connected to the plurality of capacitive sense elements, the measurement circuit configured to measure reflected impedance of an object in proximity to one or more of the plurality of capacitive sense elements, the reflected impedance measured at a sense frequency of the plurality of capacitive sense elements; and
a control and evaluation circuit electrically connected to the measurement circuit, the control and evaluation circuit configured to discriminate drops of water from living objects and one or more non-living dielectric objects based on the reflected impedance to prevent a false positive detection due to the drops of water, wherein:
the drops of water are discriminated from the living objects and the one or more non-living dielectric objects based on an angle, corresponding to the reflected impedance of the drops of water in a complex plane, being within a first angle range that is outside of a second angle range used to detect the living objects and the one or more non-living dielectric objects; and
the angle is less than 60 degrees.
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