Patent application number | Description | Published |
20130098890 | Capacitive sensing system configured for using heating element as antenna electrode - A capacitive sensing system for a heating element comprises a capacitive detector connectable to the heating element and a common mode choke for connecting the heating element with a heating current supply. The detector drives an alternating current into the heating element and produces an output depending on the capacitive load, which the alternating current is subject to. Depending on the object sensed, the load varies in a range between a minimum and a maximum value. The choke represents an inductive load in parallel of the capacitive load. The capacitive load and the inductive load contribute to a complex impedance dominated by the inductive load. A compensation capacitor arranged parallel to the choke represents an additional capacitive load also contributing to the complex impedance. The compensation capacitor is dimensioned such that the sum of additional capacitive load and maximum value amounts to at least 50% of the inductive load. | 04-25-2013 |
20130141121 | "Robust Capacitive Measurement System", - A capacitive sensing circuit is disclosed, wherein the mixer is directly connected to the sense electrode. The AC transimpedance amplifier in front of the mixer in prior art is removed and replaced by a differential DC transimpedance amplifier respectively integrator. The mixer DC offset voltage or current together with the large amplification factor required after the mixer now would result in an inacceptable DC offset at the output of the signal chain. In order to eliminate the effect of the mixer offset, the amplifying stages after the mixer are AC coupled to the mixer output and one of the signals entering the mixer is phase modulated or amplitude modu | 06-06-2013 |
20130169291 | Capacitive Measurement System with Increased Robustness Against Electro-magnetic Interference - A method for capacitive sensing comprises the steps of tagging a transmitting signal by modulating a sub-carrier on said signal using state of the art modulation techniques; demodulating said subcarrier out of useful/received signal to prove validity of said signal. | 07-04-2013 |
20130176039 | Robust Capacitive Measurement System - A capacitive sensing circuit is disclosed, wherein the transimpedance amplifier in front of the mixer in prior art is removed respectively replaced by an amplifier with low gain and consequently high dynamic range. The mixer DC offset voltage or current together with the large amplification factor required after the mixer now would result in an inacceptable DC offset at the output of the signal chain. In order to eliminate the effect of the mixer offset, the amplifying stages after the mixer are AC coupled to the mixer output and one of the signals entering the mixer is phase modulated or amplitude modulated with a known low frequency signal. An additional mixer after the AC coupled amplifying stages is driven with the same low frequency modulating signal, resulting in the wanted DC output signal responsive to the capacitance to be measured. | 07-11-2013 |
20130277351 | Capacitive sensor including resonant network - A capacitive sensor comprises a sensing antenna electrode ( | 10-24-2013 |
20130334196 | HEATING ELEMENT OPERATED AS CAPACITIVE SENSING ELECTRODE - A combined seat heater and capacitive occupancy sensor comprises a heater network including a heating element ( | 12-19-2013 |
20130334844 | CAPACITIVE OCCUPANT DETECTION SYSTEM - A capacitive occupant detection system comprises at least one sensing electrode to be arranged on the bottom side of a seat cushion, a seat heater like structure to be arranged on a top side of said seat cushion, and an evaluation unit operatively coupled to said at least one sensing electrode for determining a value representative of the capacitance between the at least one sensing electrode and the seat heater like structure. | 12-19-2013 |