Abstract: Improved switching techniques for controlling three-level current steering DAC cells are disclosed. The techniques include decoupling two current sources, implemented as field-effect transistors (FETs), of a DAC cell both from their respective bias sources and from a load for converting a zero digital input, where the decoupling is performed in a certain order. The techniques also include coupling the current sources to their respective bias sources and to the load for converting a non-zero digital input, where the coupling is also performed in a certain order. The certain order of decoupling and coupling the bias sources and the load to the current sources of a DAC cell are based on the phenomenon of current memory in FETs. Utilizing current memory when operating a DAC cell may allow reducing power consumption while preserving the high performance properties of a three-level current steering DAC.

Abstract: Z-axis microelectromechanical systems (MEMS) accelerometers are described. The z-axis MEMS accelerometers are of a teeter-totter type, having a pivoting beam suspended above a substrate. A non-uniform gap distance between the pivoting beam and the substrate is provided to increase the sensitivity of the accelerometer to z-axis acceleration. In some embodiments, the non-uniform gap distance is created by one or more substrate layers, such as one or more layers of polysilicon on the substrate above which the pivoting beam is suspended. In some embodiments, the non-uniform gap distance is created by the use of one or more bumps on the beam. In some embodiments, both substrate layers and bumps are used to provide a non-uniform gap distance for different electrodes of the accelerometer. The non-uniform gap distance may include a gap of reduced height, resulting in increased sensitivity of the accelerometer to z-axis accelerations.

Abstract: This disclosure describes techniques for extending a range of bidirectional bus communications through the use of a differential signal path. The disclosed techniques include first separating the bidirectional bus into first and second unidirectional buses that transmit and receive signals, respectively, and then communicating the signals from the first and second unidirectional buses over a differential signal path. The separation of the bidirectional bus into the first and second unidirectional buses is performed using logic circuitry that blocks or permits communication between a given one of the first and second buses and the bidirectional bus based on whichever one of the first and second buses becomes dominant first. If the logic circuitry determines that the first bus becomes dominant before the second bus, the logic circuitry permits communications between the first bus and the bidirectional bus and blocks communications between the second bus and the bidirectional bus.

Abstract: The subject disclosure provides for utilizing pulse width modulation (PWM) signaling to influence a closed loop of a shunt boost controller and reduce an imbalance of a load. The imbalance reduction helps reduce remanence of a current transformer (CT) and thereby prevent saturation of the CT. A shunt boost controller provides the control signal to control flow of current to the load. A feedback network provides a feedback signal to the shunt boost controller based on a direct current (DC) voltage and causes a power switch circuit to turn on when a magnitude of the feedback signal exceeds a threshold magnitude. The PWM generator supplies a PWM signal to cause the control signal to be provided more symmetrical to the power switch circuit and causes the power switch circuit to turn on more frequently with the control signal to reduce the imbalance of the load.

Abstract: Techniques for multiple-phase, high-boost converters are provided. In an example, a multiple-phase switched-capacitor-inductor (MPSCI) boost converter can include a first phase circuit, a second phase circuit, and a capacitor. Each of the first phase circuit and the second phase circuit can include a first switch, an inductor having a first node coupled to a first supply rail, and a second switch configured to selectively couple a second node of the inductor to a second supply rail. The capacitor can be coupled between the second node of the inductor of the second phase circuit and the first switch of the second phase circuit.

Abstract: Device for optically detecting smoke 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 a very compact housing around the smoke detector 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: A technique for improving the stability of a voltage reference is provided. The implementation of technique is simple and elegant and does not involve a noise penalty. A compensation resistor is provided on one end of a string of resistors used to set a ?VBE in a PTAT cell and to set a gain applied to the PTAT cell voltage.

Abstract: A signal acquisition or conditioning amplifier can be configured and controlled to use correlated doubling sampling (CDS) of a differential input signal, and a storage capacitor in a capacitive or other feedback network, a low power operational transconductance amplifier (OTA) capable of being powered down between CDS samplings, and which can be operated in a manner that provides good performance characteristics while still providing low or efficient power consumption. The amplifier and other signal processing circuitry can allow power to be scaled down, when less signal measurement throughput is needed, and to be scaled up, when more signal measurement throughput is needed. Such flexibility can help make the present approach useful for a wide range of signal acquisition and measurement applications. Precharging via buffer amplifiers can provide improved signal acquisition circuitry effective input impedance.

Abstract: One embodiment is an apparatus comprising a silicon-on-insulator (“SOI”) substrate comprising an insulating layer sandwiched in between a bottom silicon layer and a top silicon layer; a radiating element disposed on a top surface of the SOI substrate; and at least one cavity disposed in the SOI substrate surrounding the radiating element, wherein the at least one cavity extends from a bottom surface of the bottom silicon layer to a bottom surface of the insulating layer.

Abstract: Transimpedance amplifiers with feedforward current are provided herein. In certain embodiments, an amplifier system includes a transimpedance amplifier that amplifies an input current received at an input to generate an output voltage at an output. The amplifier system further includes a controllable current source that is coupled to the output of the transimpedance amplifier, and operable to provide a feedforward current that changes in relation to the input current of the transimpedance amplifier. By providing a feedforward current in this manner, gain and speed performance of the transimpedance amplifier is enhanced.

Abstract: Suspended microelectromechanical systems (MEMS) devices including a stack of one or more materials over a cavity in a substrate are described. The suspended MEMS device may be formed by forming the stack, which may include one or more electrode layers and an active layer, over the substrate and removing part of the substrate underneath the stack to form the cavity. The resulting suspended MEMS device may include one or more channels that extend from a surface of the device to the cavity and the one or more channels have sidewalls with a spacer material. The cavity may have rounded corners and may extend beyond the one or more channels to form one or more undercut regions. The manner of fabrication may allow for forming the stack layers with a high degree of planarity.

Abstract: A pair of programmable state machines may be included in a transmitter integrated circuit of a scanner (e.g. a body scanner) to control the sub-circuits of the transmitter integrated circuit. The first programmable state machine may be used to control the signal processor of the transmitter that facilitates generation of a signal to be transmitted at a target, such as a user to be scanned. The second programmable state machine may be used to control the transmitter's selection of a transmission channel for transmitting the signal in which provides the signal to be transmitted to an antenna. Further, the receiver integrated circuit of the scanner may include a similar pair of programmable state machines for controlling the receive signal processor and receiver of the receiver integrated circuit. The inclusion of the state machines can reduce both the scan time and the circuit complexity of the scanner.

Abstract: An integrated device package is disclosed. The integrated device package can include a packaging structure defining a cavity. An integrated device die can be disposed at least partially within the cavity. A gel can be disposed within the cavity surrounding the integrated device. A portion of the gel can be disposed between a lower surface of the integrated device die and an upper surface of the packaging structure within the cavity.

Abstract: Herein disclosed in some embodiments is a fault detector for power amplifiers of a communication system. The fault detector can detect a portion of the power amplifiers that are in fault condition and can prevent or limit current flow to the power amplifiers in fault condition while allowing the rest of the power amplifiers to operate normally. The fault detector can further indicate which power amplifiers are in fault condition and/or the cause for the power amplifiers to be in fault condition. Based on the indication, a controller can direct communications away from the power amplifiers in fault condition and/or perform operations to correct the fault condition.

Abstract: According to one example configuration, an apparatus enhances functionality of a mobile communication device. The apparatus includes an encasement in which to retain the mobile communication device and supplemental circuitry. The supplemental circuitry is operable to: i) control an optical transmitter in the supplemental circuitry to irradiate matter under test, ii) monitor attributes of an optical signal reflected off the matter under test and received by the optical receiver; and iii) communicate the attributes of the optical signal from the supplemental circuitry to the mobile communication device over a communication link. The supplemental circuitry optionally includes multiple electrodes to further monitor attributes of the matter under test.

Abstract: Systems and methods for transferring power across an isolation barrier using an active self-synchronized rectifier are described. A rectifier as described herein may provide DC to DC power conversion with high efficiency. Furthermore, by using a microfabricated transformer or microfabricated capacitor as an isolation component, an isolation component and rectifier may be microfabricated and implemented on chip.

Abstract: The Kappa converter circuit, as introduced herein, can be configured for step-down (buck), step-up (boost), or buck-boost operation. The Kappa converter circuit exhibits lower electromagnetic interference (EMI) relative to other buck, boost, or buck-boost topologies, such as without additional input or output filter circuits. The Kappa converter circuit can have high power handling capability and less DCR loss, for example due to a distribution of current signals through respective inductors. The Kappa converter circuit includes isolating inductors at its input and ground reference nodes to help reduce signal bounce or signal pulsations at supply and ground reference busses, thereby further reducing EMI noise due to switching in the circuit. When the Kappa converter is configured for step-up operation, the converter exhibits no right-half-plane (RHP) zero.

Abstract: The disclosed technology generally relates to integrated circuit devices with wear out monitoring capability. An integrated circuit device includes a wear-out monitor device configured to record an indication of wear-out of a core circuit separated from the wear-out monitor device, wherein the indication is associated with localized diffusion of a diffusant within the wear-out monitor device in response to a wear-out stress that causes the wear-out of the core circuit.

Abstract: Aspects of this disclosure relate to a segmented receiver for a wireless communication system. The segmented receiver includes a first receiver segment and a second receiver segment configured to receive respective radio frequency signals. The radio frequency signals can be orthogonally polarized. Branch circuits in each receiver segment can provide a radio frequency signal to different mixers. The different mixers can be included in different receiver segments and receive local oscillator signals from independent local oscillators. Each receiver segment can process a different bandwidth of the radio frequency signal. Two different bandwidths of the radio frequency signal can be processed concurrently by different receiver segments.

Abstract: Described herein are techniques for improving the signal-to-noise ratio of a wireless sensor platform. The device that interrogates a wireless sensor node (an interrogator) may be configured to determine the quantity to be measured by extracting information from multiple echoes produced in response to multiple interrogation pulses or produced due to multi-path propagation. Although different echoes may have been transformed to different extents, the echoes may share unique characteristics that are specific to the wireless sensor node that produced them. Accordingly, the SNR may be improved by keeping only portions of the received signal that exhibit such characteristics. The SNR may be further improved by summing the echoes together. In some embodiments, the echoes may be summed together in a coherent fashion, thereby producing an echo having an amplitude greater than the amplitude of each of the received echoes.