Abstract: A circuit for measuring an unknown resistance of a resistive element comprises a sensor circuit to generate a differential voltage dependent on the resistance of the resistive element and a reference circuit to generate a differential reference voltage and a sigma-delta converter comprising a first stage, wherein a first capacitor is selectively coupled to one of the output terminals of the sensor circuit and a second capacitor is coupled to one of the output terminals of the reference circuit. The circuit generates logarithmically compressed values.

Abstract: A method for tuning filter parameters of a noise cancellation enabled audio system with an ear-mountable playback device comprising a speaker and a feedback noise microphone located in proximity to the speaker comprises provision of acoustic transfer functions between the speaker and the feedback noise microphone, between the speaker and an eardrum, between an ambient sound source and the eardrum and between the ambient sound source and the feedback noise microphone. The parameters of a feedback filter function, which is designed to process a feedback noise signal, are tuned. A noise cancellation performance of the audio system at the eardrum is determined based on each of the acoustic transfer functions and on the feedback filter function.

Abstract: We disclose herein an electronic device comprising: a state machine for receiving an output signal from a sensor; a comparator operatively coupled with the state machine; and a first processor operatively coupled with the comparator. The state machine is configured to receive the output signal from the at least one sensor to obtain sensor measurement data and configured to pass the obtained sensor measurement data to the comparator. The comparator is configured to process the obtained sensor measurement data into first processed sensor data, and configured to compare the first processed sensor data with a first predetermined threshold limit. The comparator is configured to inform the first processor about the obtained sensor measurement data if the first processed sensor data exceed the first predetermined threshold limit.

Abstract: We disclose herein a method for testing and/or calibrating a thermopile based device. The method comprising: applying an electrical bias of a first polarity to the thermopile based device and measuring a first value of an electrical parameter; and applying an electrical bias of a second polarity to the thermopile based device and measuring a second value of an electrical parameter.

Abstract: We disclose herein an infra-red (IR) device comprising a substrate comprising an etched cavity portion and a substrate portion; a dielectric layer disposed on the substrate. The dielectric layer comprises a dielectric membrane which is adjacent, or directly above, or below the etched cavity portion of the substrate. The device further comprises a reflective layer on or in or above or below the dielectric membrane to enhance emission or absorption of infrared light at one or more wavelengths.

Abstract: We disclose an Infrared (IR) device comprising a first substrate comprising a first cavity; a dielectric layer disposed on the first substrate; a second substrate disposed on the dielectric layer and on the opposite side of the first substrate, the second substrate having a second cavity. The device further comprises an optically transmissive layer attached to one of the first and second substrates; a further layer provided to another of the first and second substrates so that the IR device is substantially closed. Holes are provided through the dielectric layer so that a pressure in the first cavity is substantially the same level as a pressure in the second cavity.

Abstract: We disclose an array of Infra-Red (IR) detectors comprising at least one dielectric membrane formed on a semiconductor substrate comprising an etched portion; at least two IR detectors, and at least one patterned layer formed within or on one or both sides of the said dielectric membrane for controlling the IR absorption of at least one of the IR detectors. The patterned layer comprises laterally spaced structures.

Abstract: It is disclosed herein a semiconductor device and a method of manufacturing the semiconductor device. The semiconductor device is made using partly CMOS or CMOS based processing steps, and it includes a semiconductor substrate, a dielectric region over the semiconductor substrate, a heater within the dielectric region and a patterned layer of noble metal above the dielectric region. The method includes the deposition of a photoresist material over the dielectric region, and patterning the photo-resist material to form a patterned region over the dielectric region. The steps of depositing the photo-resist material and patterning the photo-resist material may be performed in sequence using similar photolithography and etching steps to those used in a CMOS process. The resulting semiconductor device is then subjected to further processing steps which ensure that a dielectric membrane and a metal structure within the membrane are formed in the patterned region over the dielectric region.

Abstract: We disclose a micro-hotplate comprising a substrate comprising an etched portion and a substrate portion and a dielectric region over the substrate. The dielectric region comprises first and second portions. The first portion is adjacent to the etched portion of the substrate and the second portion is adjacent to the substrate portion of the substrate. The micro-hotplate further comprises a heater formed in the dielectric region, and a ring structure formed within and/or over the dielectric region such that the ring structure is coupled with the first and second portions of the dielectric region.

Abstract: We disclose herein an infra-red (IR) detector comprising a substrate comprising at least one etched portion and a substrate portion; a dielectric layer disposed on the substrate. The dielectric layer comprises at least one dielectric membrane, which is adjacent to the etched portion of the substrate. The detector further comprises a first sensing area and a second sensing area each located in a dielectric membrane and a plurality of thermocouples. At least one thermocouple comprises first and second thermal junctions. The first thermal junction is located in or on the first sensing area and the second thermal junction is located in or on the second sensing area.

Abstract: We disclose herein a method for testing a batch of environmental sensors to determine the fitness for purpose of the batch of environmental sensors, the method comprising: performing a plurality of electrical test sequences to the sensor inputs of the batch of environmental sensors to measure electrical responses of the sensor outputs of the batch of environmental sensors; correlating the measured electrical responses from the batch of environmental sensors to predetermined environmental parametric ranges of at least one environmental sensor so as to define correlated electrical test limits; and determining the fitness for purpose of the batch of environmental sensors if the measured electrical responses are within the correlated electrical test limits.

Abstract: We disclose herein an environmental sensor system comprising an environmental sensor comprising a first heater and a second heater in which the first heater is configured to consume a lower power compared to the second heater. The system also comprises a controller coupled with the environmental sensor. The controller is configured to detect if a measured value of a targeted environmental parameter is present. The controller is configured to switch on at least one of the first and second heaters based on the presence and/or result of the measured value of the targeted environmental parameter.

Abstract: We disclose herein a thermal IR detector array device comprising a dielectric membrane, supported by a substrate, the membrane having an array of IR detectors, where the array size is at least 3 by 3 or larger, and there are tracks embedded within the membrane layers to separate each element of the array, the tracks also acting as heatsinks and/or cold junction regions.

Abstract: We disclose a chemical sensing device for detecting a fluid. The sensing device comprises: at least one substrate region comprising at least one etched portion; a dielectric region formed on the at least one substrate region, the dielectric region comprising at least one dielectric membrane region adjacent to the at least one etched portion; an optical source for emitting an infra-red (IR) signal; an optical detector for detecting the IR signal emitted from the optical source; one or more further substrates formed on or under the dielectric region, said one or more further substrates defining an optical path for the IR signal to propagate from the optical source to the optical detector. At least one of the optical source and optical detector is formed in or on the dielectric membrane region.