Abstract: There is disclosed herein examples of systems and methods for compressing a signal. Samples of the signal can be segmented and the samples within each of the segments can be averaged to produce a value that can represent the samples within the segment. The number of samples to average in each segment may be determined based on an error threshold, such that the number of samples being averaged can be maximized to produce less data to be transmitted while maintaining the representation of the samples within the error threshold. In some embodiments, a signal can be separated into a timing reference, a representative periodic function, and a highly compressible error signal. The error signal can be utilized for reproducing a representation of the signal.

Abstract: Transconductor circuits with programmable tradeoff between bandwidth and flicker noise are disclosed. An example circuit includes an input port, an output port, a plurality of transistors, and a switch arrangement that includes a plurality of switches, configured to change coupling between the input port, the output port, and the transistors to place the transconductor circuit in a first or a second mode of operation. An input capacitance of the transconductor circuit operating in the first mode is larger than when the transconductor circuit is operating in the second mode. In the first mode, having a larger input capacitance results in a decreased flicker noise because the amount of flicker noise is inversely proportional to the input capacitance. In the second mode, having a smaller input capacitance leads to an increased flicker noise but that is acceptable for wide-bandwidth applications because wide-bandwidth signals may be less sensitive to flicker noise.

Abstract: Device for improving an optical detecting smoke apparatus and implementing thereof. Apparatus and methods for detecting the presence of smoke in a small, long-lasting smoke detector are disclosed. Specifically, the present disclosure shows how to build one or more optimized blocking members in a smoke detector to augment signal to noise ratio. This is performed while keeping the reflections from the housing structure to a very low value while satisfying all the other peripheral needs of fast response to smoke and preventing ambient light. This allows very small measurements of light scattering of the smoke particles to be reliable in a device resistant to the negative effects of dust. In particular, geometrical optical elements, e.g., cap and optical defection elements, are disclosed.

Abstract: Time of Flight (ToF) depth image processing methods. Depth edge preserving filters are disclosed with superior performance to standard edge preserving filters applied to depth maps. In particular, depth variance is estimated and used to filter while preserving depth edges. In doing so, filter strength is calculated which can be used as an edge detector. A confidence map is generated with low confidence at pixels straddling a depth edge, and which reflects the reliability of the depth measurement at each pixel.

Abstract: Couplers for selectively coupling in-plane and out-of-plane motion between moving masses are provided herein. In particular, aspects of the present application provide for a coupler configured to couple in-plane motion between moving masses while decoupling out-of-plane motion between the moving masses. The selective couplers as described herein may be used in a device, such as a microelectromechanical systems (MEMS) inertial sensor. In some embodiments, a MEMS inertial sensor comprises a first mass configured to move in-plane, a second mass configured to move in-plane and out-of-plane, and a coupler coupling the first and second masses and comprising two levers coupled to an anchor point by respective tethers and coupled to each other by a spring.

Abstract: Herein disclosed are systems and circuitry for protecting against overdrive and electrostatic discharge. For example, protection circuitry may include field effect transistors to discharge overdrive outside of an operational voltage range of a circuit in some embodiments to prevent damage to the circuit. Further, the protection circuitry may utilize diode features inherent in the field effect transistors to protect against electrostatic discharge in some embodiments. The circuitry may be implemented in radio frequency sampling analog-to-digital converters and can provide for single-ended signal input and/or output for the analog-to-digital converters.

Abstract: Embodiments of the present disclosure relate to cellular technology applications of beamforming performed in the digital domain. In one aspect, an RF system for performing digital beamforming on a per-carrier basis is disclosed, where different phase and/or amplitude adjustments are applied to signals of different frequency ranges (i.e., to different carrier signals). In another aspect, an RF system for performing digital beamforming on a per-antenna basis is disclosed, where different phase and/or amplitude adjustments are applied to signals transmitted from or received by different antennas. In some embodiments, an RF system may be configured to implement both digital beamforming on a per-carrier basis and digital beamforming on a per-antenna basis. The RF systems disclosed herein allow implementing programmable beamforming in the digital domain in a manner that is significantly less complex than conventional implementations.

Abstract: Aspects of the present application allow for measurement of a calibrated resistance for a resistive film in a sensing element, such that effects from contact resistance and background resistance drifts due to factors such as temperature, strain or aging can be reduced or eliminated. In some embodiments, by taking a plurality of two-terminal resistance measurements between various pairs of electrodes on a resistive film, a contact-resistance-independent resistance of a reference portion of the resistive film can be determined. Further, a contact-resistance-independent resistance of a sensing portion of the resistive film can be determined based on a plurality of two-terminal resistance measurements between pairs of electrodes. The resistance of the reference portion can be removed from the measured resistance of the sensing portion, such that variations in the reference portion resistance that are not caused by a sensed environmental condition may be compensated.

Abstract: Apparatus and methods for control and calibration of tunable filters are provided. In certain embodiments, a tunable filter includes at least one controllable component (for instance, a controllable inductor or a controllable capacitor) having a value that changes or adjusts a center frequency of the tunable filter. For example, the controllable component can correspond to a controllable inductor or a controllable capacitor of an inductor-capacitor (LC) resonator of the tunable filter. The tunable filter further includes a control circuit implemented with an approximation function for estimating a value of the controllable component for achieving a desired center frequency indicated by a frequency control signal.

Abstract: Apparatus and methods for tunable filtering are provided. In certain embodiments, a tunable filter is implemented using one or more controllable capacitors formed on a semiconductor die and using one or more shielded integrated inductors formed on a secondary circuit board that attaches to a carrier circuit board. Additionally, the shielded integrated inductors are formed from patterned metallization layers of the secondary circuit board, and shielding is provided on the secondary circuit board and/or the carrier circuit board to shield the inductors from the semiconductor die and/or other components.

Abstract: Columnar multi-axis microelectromechanical systems (MEMS) devices (such as gyroscopes) balanced against undesired linear and angular vibration are described herein. In some embodiments, the columnar MEMS device may comprise at least two multiple-mass columns, each having at least three proof masses and being configured to sense rotation about a respective axis. The motion and mass of the proof masses may be controlled to achieve linear and rotational balancing of the MEMS device. The columnar MEMS device may further comprise one or more modular drive structures disposed alongside each multiple-mass column to facilitate displacement of the proof masses of a respective column. The MEMS devices described herein may be used to sense roll, yaw, and pitch angular rates.

Abstract: A MEMS device is provided comprising a mass configured to move along a first axis and a second axis substantially perpendicular to the first axis; a drive structure coupled to the mass and configured to cause the mass to move along the first axis; a sense structure coupled to the mass and configured to detect motion of the mass along the second axis; a stress relief structure coupled to one of the drive structure or the sense structure; and at least one anchor coupled to an underlying substrate of the MEMS device, wherein the stress relief structure is coupled to the at least one anchor and the at least one anchor is disposed outside of the stress relief structure.

Abstract: A stress-isolated microelectromechanical systems (MEMS) device and a method of manufacture of the stress-isolated MEMS device are provided. MEMS devices may be sensitive to stress and may provide lower performance when subjected to stress. A stress-isolated MEMS device may be manufactured by etching a trench and/or a cavity in a first side of a substrate and subsequently forming a MEMS device on a surface of a platform opposite the first side of the substrate. Such a stress-isolated MEMS device may exhibit better performance than a MEMS device that is not stress-isolated. Moreover, manufacturing the MEMS device by first forming a trench and cavity on a backside of a wafer, before forming the MEMS device on a suspended platform, provides increased yield and allows for fabrication of smaller parts, in at least some embodiments.

Abstract: A MEMS device is provided comprising a substrate; a proof mass coupled to the substrate and configured to move along a resonator axis; a drive structure comprising at least one electrode and configured to drive the proof mass to move along the resonator axis; and a pivoting linkage coupled to the proof mass at first and second ends of the pivoting linkage, the first end comprising a first fixed pivot and the second end comprising a second fixed pivot, the pivoting linkage comprising: a first bar configured to pivot about the first fixed pivot and a first dynamic pivot; a second bar configured to pivot about the second fixed pivot and a second dynamic pivot; and a third bar configured to pivot about the first dynamic pivot and the second dynamic pivot, wherein the proof mass moves along the resonator axis when the pivoting linkage pivots.

Abstract: System and apparatus for measuring biopotential and implementation thereof. A device for mitigating electromagnetic interference (EMI) thereby increasing signal-to-noise ratio is disclosed. Specifically, the present disclosure relates to an elegant, novel circuit for measuring a plurality of biopotentials in useful in a variety of medical applications. This allows for robust, portable, low-power, higher S/N devices which have historically required a much bigger footprint.

Abstract: Columnar multi-axis microelectromechanical systems (MEMS) devices (such as gyroscopes) balanced against undesired linear and angular vibration are described herein. In some embodiments, the columnar MEMS device may comprise at least two multiple-mass columns, each having at least three proof masses and being configured to sense rotation about a respective axis. The motion and mass of the proof masses may be controlled to achieve linear and rotational balancing of the MEMS device. The columnar MEMS device may further comprise one or more modular drive structures disposed alongside each multiple-mass column to facilitate displacement of the proof masses of a respective column. The MEMS devices described herein may be used to sense roll, yaw, and pitch angular rates.

Abstract: An example current mirror arrangement includes a current mirror circuit, configured to receive an input current signal at an input transistor Q1 and output a mirrored signal at an output transistor Q2. The arrangement further includes a buffer amplifier circuit, having an input coupled to Q1 and an output coupled to Q2. The offset of the buffer amplifier circuit can be adjusted by including circuitry for an input or an output side offset adjustment or by implementing the buffer amplifier circuit as a diamond stage with individually controlled current sources for each of the transistors of the diamond stage. Providing an adjustable offset buffer in a current mirror arrangement may advantageously allow benefiting from the use of a buffer outside of a feedback loop of a current mirror, while being able to reduce the buffer offset due to mismatch between master and slave sides of the current mirror circuit.

Abstract: One embodiment is a multi-analyte molecular sensing system designed for implantation in a body of a subject, the sensing system including an implant comprising a flexible substrate having a plurality of electronics systems disposed thereon; a sensor array comprising multiple sensors disposed on the flexible substrate; a sensor protection mechanism for providing selective protection and exposure of one or more of the sensors; a power system for providing power to the electronics systems; a data communication system for communicating with one or more external devices; and a biocompatible housing for protecting the implant.

Abstract: Disclosed herein are some examples of analog-to-digital converters (ADCs) that can perform auto-zeroing with amplifying a signal for improvement of a signal-to-noise ratio. The ADCs may produce a first digital code to represent an analog input signal and a second digital code based on a residue from the first digital code, and may combine the first digital code and the second digital code to produce a digital output code to represent the analog input signal. The ADC may utilize a first observation and a second observation of an analog residue value representing the residue to produce the second digital code.

Abstract: Apparatus and methods for clock synchronization and frequency translation are provided herein. Clock synchronization and frequency translation integrated circuits (ICs) generate one or more output clock signals having a controlled timing relationship with respect to one or more reference signals. The teachings herein provide a number of improvements to clock synchronization and frequency translation ICs, including, but not limited to, reduction of system clock error, reduced variation in clock propagation delay, lower latency monitoring of reference signals, precision timing distribution and recovery, extrapolation of timing events for enhanced phase-locked loop (PLL) update rate, fast PLL locking, improved reference signal phase shift detection, enhanced phase offset detection between reference signals, and/or alignment to phase information lost in decimation.