4-points phase and sensitivity estimation algorithm and related architecture
Granted: April 8, 2025
Patent Number:
12270652
An algorithm and architecture for sense transfer function estimation injects one or more test signals from a signal generator into a MEMS gyroscope to detect an output signal (e.g., proof mass output sense signal), including an in-phase (e.g., Coriolis) component and a quadrature component. The in-phase and quadrature components are encoded with reference signals to determine phase and/or gain variation and are processed via a variety of components (e.g., matrix rotation, digital gain,…
Ultrasonic cliff detection and depth estimation using tilted sensors
Granted: April 1, 2025
Patent Number:
12265186
A robotic cleaning appliance includes a housing to which is coupled a surface treatment item and a sensor assembly with first and second transducers and an acoustic interface. The first sonic transducer transmits sonic signals through an acoustic interface and out of a first acoustic opening toward a surface beneath the robotic cleaning appliance. The sonic signals reflect from the surface as corresponding returned signals received by the second sonic transducer via a second acoustic…
Method and system for fabricating a MEMS device
Granted: March 25, 2025
Patent Number:
12258266
A method includes forming a bumpstop from a first intermetal dielectric (IMD) layer and forming a via within the first IMD, wherein the first IMD is disposed over a first polysilicon layer, and wherein the first polysilicon layer is disposed over another IMD layer that is disposed over a substrate. The method further includes depositing a second polysilicon layer over the bumpstop and further over the via to connect to the first polysilicon layer. A standoff is formed over a first…
Interleaved CIC filter
Granted: March 18, 2025
Patent Number:
12255598
An interleaved cascaded integrator-comb (“CIC”) filter receives an interleaved sensor output signal, including a plurality of digitized sensor signals at an input clock rate. An integrator of the interleaved CIC filter processes the interleaved signal to output an integrated interleaved signal. A downsampler of the interleaved CIC filter buffers portions of the integrated interleaved corresponding to a decimation rate for the interleaved signal. The portions of the signals are…
Ultrasonic liquid level sensing
Granted: March 18, 2025
Patent Number:
12253401
Systems and methods for ultrasonic liquid level sensing. A circuit causes an ultrasonic transducer to transmit a sequence of ultrasonic pulses and receive a sequence of reflected signals. Each reflected signal includes at least one first reflection associated with at least one non-moveable surface and at least one second reflection associated with a moveable surface. A digital controller, for each reflected signal: determines at least one of a magnitude and a variance of the respective…
Event activity detection signaling
Granted: March 4, 2025
Patent Number:
12245004
Acoustic and other activity detection signaling is provided herein. Operations of a method can include determining a micro-electromechanical system (MEMS) device is no longer in an initialization state and receiving a first signal that instructs the MEMS device to perform event activity detection. The method can also include receiving one or more event signals and determining that an event signal of one or more event signals satisfies a defined event characteristic. The method can also…
Acoustic activity detection
Granted: February 25, 2025
Patent Number:
12238481
Acoustic activity detection is provided herein. Operations of a method can include receiving an acoustic signal at a micro-electromechanical system (MEMS) microphone. Based on portions of the acoustic signal being determined to exceed a threshold signal level, output pulses are generated. Further, the method can include extracting information representative of a frequency of the acoustic signal based on respective spacing between rising edges of the output pulses.
Apparatus and system for tuning the resonant frequency of a piezoelectric micromachined ultrasonic transducer
Granted: February 18, 2025
Patent Number:
12226801
The teachings of the present disclosure enable the manufacture of one or more piezoelectric micromachined ultrasonic transducers (PMUTs) having a resonant frequency of a specific target value and/or substantially matched resonant frequencies. In accordance with the present disclosure, a flexible membrane of a PMUT is modified to impart a desired parameter profile for stiffness and/or mass to tune its resonant frequency to a target value. The desired parameter profile is achieved by…
Drive and sense balanced, semi-coupled 3-axis gyroscope
Granted: February 18, 2025
Patent Number:
12228404
A dynamically balanced 3-axis gyroscope architecture is provided. Various embodiments described herein can facilitate providing linear and angular momentum balanced 3-axis gyroscope architectures for better offset stability, vibration rejection, and lower part-to-part coupling.
Robust inertial sensor self-test
Granted: February 18, 2025
Patent Number:
12227409
An inertial sensor such as a MEMS accelerometer or gyroscope has a proof mass that is driven by a self-test signal, with the response of the proof mass to the self-test signal being used to determine whether the sensor is within specification. The self-test signal is provided as a non-periodic self-test pattern that does not correlate with noise such as environmental vibrations that are also experienced by the proof mass during the self-test procedure. The sense output signal…
Clocking scheme for reduced noise in continuous-time sigma-delta adcs preliminary class
Granted: January 14, 2025
Patent Number:
12199629
A circuit for a feedback system incorporates a gating mechanism to reduce flicker noise (e.g., a source for bias instability within a MEMS device) at a digital output. The gating mechanism generates a gating pulse with a delay period (e.g., a common, or fixed, delay including symmetrical rising and falling edge delays) that overrides internal delays (e.g., asymmetrical rising and falling edge delays) of a phase generator to prevent propagation delay (e.g., delay affected by jitter) from…
Microelectromechanical system microphone array capsule
Granted: January 7, 2025
Patent Number:
12192704
The present invention relates to a microelectromechanical system (MEMS) microphone array capsule. In one embodiment, a MEMS microphone includes a MEMS microphone die; an acoustic sensor array formed into the MEMS microphone die, the acoustic sensor array comprising a plurality of MEMS acoustic sensor elements, wherein respective ones of the plurality of MEMS acoustic sensor elements are tuned to different resonant frequencies; and an interconnect that electrically couples the acoustic…
Method and system for fabricating a MEMS device
Granted: December 31, 2024
Patent Number:
12180069
A device includes a substrate and an intermetal dielectric (IMD) layer disposed over the substrate. The device also includes a first plurality of polysilicon layers disposed over the IMD layer and over a bumpstop. The device also includes a second plurality of polysilicon layers disposed within the IMD layer. The device includes a patterned actuator layer with a first side and a second side, wherein the first side of the patterned actuator layer is lined with a polysilicon layer, and…
Sensor with integrated heater
Granted: December 31, 2024
Patent Number:
12180067
A device includes a microelectromechanical system (MEMS) sensor die comprising a deformable membrane, a MEMS heating element, and a substrate. The MEMS heating element is integrated within a same layer and a same plane as the deformable membrane. The MEMS heating element surrounds the deformable membrane and is separated from the deformable membrane through a trench. The MEMS heating element is configured to generate heat to heat up the deformable membrane. The substrate is coupled to…
MEMS sensor with compensation of residual voltage
Granted: December 24, 2024
Patent Number:
12174215
A microelectromechanical (MEMS) sensor, such as an accelerometer, has one more proof masses that respond to movement of the sensor, the movement of which is measured based on a distance between the one or more proof masses and on one or more sense electrodes. The accelerometer also has a plurality of auxiliary electrodes and a signal generator configured to apply an auxiliary signal having a first harmonic frequency to the plurality of auxiliary electrodes. Circuitry receives a sensed…
Fixed-fixed membrane for microelectromechanical system microphone
Granted: December 17, 2024
Patent Number:
12170869
The present invention relates to a fixed-fixed membrane for a microelectromechanical system (MEMS) microphone. In one embodiment, a MEMS acoustic sensor includes a substrate; a membrane situated parallel to the substrate; and at least one vent formed into the membrane, wherein the at least one vent is a curved opening in the membrane, and wherein the at least one vent is disposed substantially along a length of the membrane.
Piezoelectric micromachined transducer and device
Granted: December 10, 2024
Patent Number:
12161507
An ultrasonic transducer device comprises a piezoelectric micromachined ultrasonic transducer (PMUT), a transmitter with first and second differential outputs, and a controller. The PMUT includes a membrane layer. A bottom electrode layer, comprising a first bottom electrode and a second bottom electrode, is disposed above the membrane layer. The piezoelectric layer is disposed above the bottom electrode layer. The top electrode layer is disposed above the piezoelectric layer and…
Adaptive sensor filtering
Granted: December 3, 2024
Patent Number:
12158460
Environmental conditions affecting a sensor having a thermal coefficient are compensated by applying an adaptive filter to an environmental condition reference signal. The resulting adaptive cancellation signal may be used to provide feedback control to a first heating element.
Selective self-assembled monolayer patterning with sacrificial layer for devices
Granted: November 12, 2024
Patent Number:
12139397
Selective self-assembled monolayer patterning with sacrificial layer for devices is provided herein. A sensor device can include a handle layer and a device layer that comprises a first side and a second side. First portions of the first side are operatively connected to defined portions of the handle layer. At least one area of the second side comprises an anti-stiction area formed with an anti-stiction coating. The device can also include a Complementary Metal-Oxide-Semiconductor…
Pressure sensor with high stability
Granted: November 12, 2024
Patent Number:
12139398
A method includes depositing a passivation layer on a substrate; depositing and patterning a first polysilicon layer on the passivation layer; depositing and patterning a first oxide layer on the first polysilicon layer forming a patterned first oxide layer; depositing and patterning a second polysilicon layer on the patterned first oxide layer. A portion of the second polysilicon layer directly contacts a portion of the first polysilicon layer. A portion of the patterned second…
