Abstract: Aspects of the subject technology relate to an apparatus including a housing and a substrate. The apparatus further includes a sensor, an integrated circuit mounted on the substrate, and one or more heating elements configured to adjust a temperature of the sensor to facilitate measurement of temperature sensitivity and calibration of the sensor.

Abstract: A wireless communication device includes a pressure sensor to generate a first signal in response to a pressure variation. A variable offset capacitor is coupled in parallel with the pressure sensor. A first analog-to-digital converter (ADC) is coupled to the variable offset capacitor and to convert the first signal to a digital signal. The pressure sensor is a capacitive pressure sensor. The variable offset capacitor is a digitally controlled variable capacitor and the ADC is a low-resolution and low-power ADC.

Abstract: An electronic device can include a housing defining an internal volume and a pressure sensor assembly disposed in the internal volume and in communication with an ambient environment. The pressure sensor assembly can include a structure at least partially enclosing a sensor volume, a pressure sensor affixed to a die disposed in the sensor volume, and an exposed moisture detection conductor positioned in the sensor volume.

Abstract: A portable communication device includes one or more optical detectors to generate an analog signal in response to a change in an intra-cavity or an emitted optical power of a light source due to light backscattered from a particle and an application-specific integrated circuit (ASIC). The particle is illuminated via a light source. The ASIC includes an analog-to-digital converter (ADC) circuit, a digital delay circuit, a particle detector module and a processor. The ADC converts the analog signal to a digital signal. The digital delay circuit can store the digital signal for a predetermined or dynamically variable time interval. The particle detector module can analyze the digital signal and can generate an enable signal upon detecting a particle signature in the digital signal. The processor is coupled to the digital delay circuit and can start processing the digital signal in response to the enable signal.

Abstract: Aspects of the subject technology relate to electronic devices with pressure sensors. A pressure sensor in a portable electronic device may include an integrated heater or may be co-operated with an external heater for the pressure sensor. The heater may be operated to heat some or all of the pressure sensor for pressure sensor testing, calibration, or temperature-controlled pressure sensing operations.

Abstract: A pressure sensing module for an electronic device includes a substrate and a module housing coupled to the substrate. The module housing defines a first chamber and a second chamber. The second chamber is separate from the first chamber. The first chamber is configured to connect to an environment around an electronic device. The second chamber is configured to connect to an internal volume of the housing of the electronic device. A first pressure sensing element is electrically coupled to the substrate and disposed in the first chamber and is operative to detect an external pressure around the electronic device. A second pressure sensing element is electrically coupled to the substrate and disposed in the second chamber and is operative to detect an internal pressure within the electronic device housing.

Abstract: An electronic device can include a housing defining an internal volume and a pressure sensor assembly disposed in the internal volume and in communication with an ambient environment. The pressure sensor assembly can include a structure at least partially enclosing a sensor volume, a pressure sensor affixed to a die disposed in the sensor volume, and an exposed moisture detection conductor positioned in the sensor volume.

Abstract: A quadrature ADC feedback compensation system and method for MEMS gyroscope is disclosed. In an embodiment, a MEMS gyroscope comprises an analog processing chain including a drive circuit for generating an analog drive signal and a sense circuit that is configured to generate an analog rate signal and an analog quadrature signal in response to a change in capacitance output by the MEMS gyroscope. A compensation circuit coupled to the sense circuit is configured to null the analog quadrature signal using the analog drive signal and a compensation value, and to adaptively compensate, in a digital processing chain, a quadrature-induced rate offset of a digital rate signal over temperature using a digital quadrature signal, the compensation value and temperature data.

Abstract: An apparatus with embedded water detection and heater includes a substrate including a number of conductive traces and a lid including multiple electrodes. Each electrode is coupled to at least one of the conductive traces through vias. A sensor is placed inside a cavity of the lid and is electrically coupled to one or more conductive traces of the substrate. A gel at least partially fills the lid and covers the sensor. The presence of water on the apparatus is detected by measuring a dielectric permittivity between at least two of the plurality of electrodes, and the electrodes can generate heat to eliminate the water.

Abstract: Aspects of the subject technology relate to a circuit for reducing random-telegraph noise in bandgap circuits. The circuit includes a number of diodes coupled in parallel at their respective first nodes to a ground potential. A number of switches are coupled to respective second nodes of the diodes. The circuit further includes a first resistor and a resistor voltage divider. The first node of the first resistor is coupled to a first node of a current source, and the first node of the resistor voltage divider is coupled to the first node of the current source. The switches are used to implement cyclic switching of the diodes in response to a train of pulses. An output voltage of the circuit is derived between a mid-node of the resistor voltage divider and a second node of the first resistor.

Abstract: An architecture is disclosed for an angular rate sensor that includes a duty-cycled phase shifter for generating a clock with high resolution delay for use in synchronized demodulation of a sensor output signal. In an embodiment, a sensor comprises: a mechanical resonator; a drive circuit coupled to the mechanical resonator and operable to actuate the mechanical resonator into resonant vibration; a sense circuit mechanically coupled to the mechanical resonator, the sense circuit operable to generate a sense signal having an in-phase signal component and a quadrature signal component; a demodulator circuit operable to receive the sense signal and a first clock for demodulating the sense signal to separate the in-phase signal component from the quadrature signal component; and a duty-cycled phase shifter coupled to the demodulator, the duty-cycled phase shifter operable to generate the first clock.

Abstract: A portable communication device includes one or more optical detectors to generate an analog signal in response to a change in an intra-cavity or an emitted optical power of a light source due to light backscattered from a particle and an application-specific integrated circuit (ASIC). The particle is illuminated via a light source. The ASIC includes an analog-to-digital converter (ADC) circuit, a digital delay circuit, a particle detector module and a processor. The ADC converts the analog signal to a digital signal. The digital delay circuit can store the digital signal for a predetermined or dynamically variable time interval. The particle detector module can analyze the digital signal and can generate an enable signal upon detecting a particle signature in the digital signal. The processor is coupled to the digital delay circuit and can start processing the digital signal in response to the enable signal.

Abstract: A microelectromechanical system (MEMS) ambient pressure and acoustic sensor including an enclosure having an enclosure wall that defines an interior chamber and an acoustic input opening to the interior chamber, a moving structure positioned within the interior chamber and being acoustically coupled to the acoustic input opening. The moving structure having an acoustic sensing portion that is movable in response to an acoustic pressure input and an ambient pressure sensing portion that is movable in response to an ambient pressure input. The sensor further including a circuit electrically coupled to the moving structure and that is operable to determine an acoustic output and an ambient pressure output based on a movement of the moving structure.

Abstract: A pressure sensing module for an electronic device includes a substrate and a module housing coupled to the substrate. The module housing defines a first chamber and a second chamber. The second chamber is separate from the first chamber. The first chamber is configured to connect to an environment around an electronic device. The second chamber is configured to connect to an internal volume of the housing of the electronic device. A first pressure sensing element is electrically coupled to the substrate and disposed in the first chamber and is operative to detect an external pressure around the electronic device. A second pressure sensing element is electrically coupled to the substrate and disposed in the second chamber and is operative to detect an internal pressure within the electronic device housing.

Abstract: An apparatus with embedded water detection and heater includes a substrate including a number of conductive traces and a lid including multiple electrodes. Each electrode is coupled to at least one of the conductive traces through vias. A sensor is placed inside a cavity of the lid and is electrically coupled to one or more conductive traces of the substrate. A gel at least partially fills the lid and covers the sensor. The presence of water on the apparatus is detected by measuring a dielectric permittivity between at least two of the plurality of electrodes, and the electrodes can generate heat to eliminate the water.

Abstract: A wireless communication device includes a pressure sensor to generate a first signal in response to a pressure variation. A variable offset capacitor is coupled in parallel with the pressure sensor. A first analog-to-digital converter (ADC) is coupled to the variable offset capacitor and to convert the first signal to a digital signal. The pressure sensor is a capacitive pressure sensor. The variable offset capacitor is a digitally controlled variable capacitor and the ADC is a low-resolution and low-power ADC.

Abstract: A quadrature ADC feedback compensation system and method for MEMS gyroscope is disclosed. In an embodiment, a MEMS gyroscope comprises an analog processing chain including a drive circuit for generating an analog drive signal and a sense circuit that is configured to generate an analog rate signal and an analog quadrature signal in response to a change in capacitance output by the MEMS gyroscope. A compensation circuit coupled to the sense circuit is configured to null the analog quadrature signal using the analog drive signal and a compensation value, and to adaptively compensate, in a digital processing chain, a quadrature-induced rate offset of a digital rate signal over temperature using a digital quadrature signal, the compensation value and temperature data.

Abstract: Aspects of the subject technology relate to electronic devices with pressure sensors. A pressure sensor in a portable electronic device may include an integrated heater or may be co-operated with an external heater for the pressure sensor. The heater may be operated to heat some or all of the pressure sensor for pressure sensor testing, calibration, or temperature-controlled pressure sensing operations.

Abstract: A microelectromechanical system (MEMS) ambient pressure and acoustic sensor including an enclosure having an enclosure wall that defines an interior chamber and an acoustic input opening to the interior chamber, a moving structure positioned within the interior chamber and being acoustically coupled to the acoustic input opening. The moving structure having an acoustic sensing portion that is movable in response to an acoustic pressure input and an ambient pressure sensing portion that is movable in response to an ambient pressure input. The sensor further including a circuit electrically coupled to the moving structure and that is operable to determine an acoustic output and an ambient pressure output based on a movement of the moving structure.

Abstract: An architecture is disclosed for an angular rate sensor that includes a duty-cycled phase shifter for generating a clock with high resolution delay for use in synchronized demodulation of a sensor output signal. In an embodiment, a sensor comprises: a mechanical resonator; a drive circuit coupled to the mechanical resonator and operable to actuate the mechanical resonator into resonant vibration; a sense circuit mechanically coupled to the mechanical resonator, the sense circuit operable to generate a sense signal having an in-phase signal component and a quadrature signal component; a demodulator circuit operable to receive the sense signal and a first clock for demodulating the sense signal to separate the in-phase signal component from the quadrature signal component; and a duty-cycled phase shifter coupled to the demodulator, the duty-cycled phase shifter operable to generate the first clock.