Abstract: Some or all of a comparator circuit of an analog-to-digital converter (ADC) circuit can be efficiently repurposed or reused for residue amplification for efficient noise-shaping, e.g., in a noise-shaping feedback configuration. A preamplifier portion of a comparator circuit in an oversampling ADC can be re-purposed to provide an amplifier to amplify or otherwise modify a residue left after the bit trials of a conversion cycle. The amplified or modified residue can then be used elsewhere, for example, for noise-shaping by applying a noise transfer function (NTF), a result of which can then be fed back (e.g., summed with the next sampled input at an input of the comparator circuit for use in the N bit trials of the next ADC cycle).

Abstract: A differential pair gain stage is disclosed. In one embodiment, the gain stage includes a differential pair of depletion-mode transistors, including a first and a second n-type transistor. In certain embodiments of the invention, the depletion mode transistor may be GaN (gallium nitride) field effect transistors. The gain stage includes an active load including one or more depletion mode transistors electrically coupled to at least one of the drains of depletion mode transistors of the differential pair. The active load may include a source follower for maintaining the AC voltages at the drains of the differential pair at a constant value and may further include a casocde stage for setting a fixed drain source voltage across the output transistors to increase the output impedance and gain of the stage.

Abstract: A microelectronic circuit having at least one component adjacent a carrier that is not a semiconductor or sapphire. The circuit includes a component bearing stack of one or more layers having one or more passive components, which are adjacent or bonded to the carrier. In certain embodiments, the circuit also includes an etch stop layer of a material having a slower etch rate than silicon and a bond layer bonding the carrier and the component bearing one or more layers.

Abstract: A multibit flash quantizer circuit, such as included as a portion of delta-sigma conversion circuit, can be operated in a dynamic or configurable manner. Information indicative of at least one of an ADC input slew rate or a prior quantizer output code can be used to establish a flash quantizer conversion window. Within the selected conversion window, comparators in the quantizer circuit can be made active. Comparators outside the conversion window can be made dormant, such as depowered or biased to save power. An output from such dormant converters can be preloaded and latched. In this manner, full resolution is available without requiring that all comparator circuits within the quantizer remain active at all times.

Abstract: Multi-step ADCs performs multi-step conversion by generating a residue for a subsequent stage to digitize. To generate a residue, a stage in the multi-step ADC would reconstruct the input signal to the stage using a feedforward digital to analog converter (DAC). Non-linearities in the DAC can directly affect the overall performance of the multi-step ADC. To reduce power consumption and complexity of analog circuit design, digital background calibration schemes are implemented to address the non-linearities. The non-linearities that the calibration schemes address can include reference, DAC, and quantization non-linearities.

Abstract: Improved track and hold (T/H) circuits can help analog-to-digital converters (ADCs) achieve higher performance and lower power consumption. The improved T/H circuits can drive high speed and interleaved ADCs, and the design of the circuits enable additive and multiplicative pseudo-random dither signals to be injected in the T/H circuits. The dither signals can be used to calibrate (e.g., linearize) the T/H circuits and the ADC(s). In addition, the dither signal can be used to dither any remaining non-linearity, and to calibrate offset/gain mismatches in interleaved ADCs. The T/H circuit design also can integrate an amplifier in the T/H circuit, which can be used to improve the signal-to-noise ratio (SNR) of the ADC or to act as a variable gain amplifier (VGA) in front of the ADC.

Abstract: This disclosure relates to data communication networks. An example data communication apparatus includes physical (PHY) layer circuitry that includes transceiver circuitry, decoder circuitry, and a signal analysis unit. The transceiver circuitry receives encoded data symbols via a network link. The received encoded data symbols are encoded using trellis coded modulation (TCM). The decoder circuitry decodes the received encoded data symbols using maximum-likelihood (ML) decoding to map a received symbol sequence to an allowed symbol sequence using a trace-back depth. A trace-back depth value is a number of symbols in the received symbol sequence used by the ML decoding to identify the allowed symbol sequence from the received symbol sequence. The signal analysis unit determines one or more link statistics of the network link, and sets the trace-back depth value according to the one or more link statistics.

Abstract: A device for controlling an electronic switch between a power supply and a load includes a sensing circuit to measure a current to the load and a control circuit to control operation of the electronic switch if the current exceeds a current limit. The control circuit includes a normal current circuit to output a first switch control current to the electronic switch and a boost current circuit to output a second switch control current to the electronic switch, the first switch control current being higher than the second switch control current.

Abstract: An embodiment of a communication system for transmitting and receiving data across an isolation barrier may include a communication circuit connected to an isolator at a first side of the isolation barrier, the communication circuit having a transmit circuit to drive a first data signal onto the isolator based on input data received by the communication circuit, a receive circuit to receive a second data signal from the isolator and produce output data based on the received second data signal, and a control circuit to control the transmit and receive circuits to provide time division multiplexing of the first and second data signals.

Abstract: Apparatus and methods for frequency tuning of rotary traveling wave oscillators (RTWOs) are provided herein. In certain configurations, distributed quantized tuning is used to tune a frequency of the RTWO. The RTWO includes a plurality of segments distributed around the RTWO's ring, and the segments include tuning capacitors and other circuitry. The distributed quantized frequency tuning is used to control the tuning capacitors in the RTWO's segments using separately controllable code values, thereby enhancing the RTWO's frequency step size or resolution. Moreover, in configurations including multiple RTWO rings that are locked to one another to reduce phase noise, the distributed quantized frequency tuning can be used to separately set the tuning capacitors across multiple RTWO rings that are coupled to one another.

Abstract: A charge injection compensation circuit compensates for charge injection by a field-effect transistor (FET) switch regardless of a supply voltage. The charge injection compensation circuit includes a main switch that injects charge into an electronic circuit when switched off, and a charge storage device that stores the injected charge until it can be dissipated to a dissipating node. Upon the main switch being controlled to switch off, a pulse generator circuit controls a charge storage switch to switch on to transfer the charge injected from the main switch to the charge storage device and then switch off. A dissipation circuit dissipates the charge from the charge storage device to a dissipating node.

Abstract: A system comprises a plurality of power supplies, wherein a power supply provides a supply voltage rail to a voltage domain of the system; a plurality of power supply voltage sequencer devices electrically coupled to multiple power supplies of the plurality of power supplies, wherein a voltage sequencer device is configured to activate the multiple power supplies in a specified sequence; and a bus electrically coupled to the plurality of power supply voltage sequencer devices, wherein the bus is configured to communicate state information of the plurality of power supply voltage sequencer devices.

Abstract: A successive-approximation-register analog-to-digital converter (SAR ADC) typically includes circuitry for implementing bit trials that converts an analog input to a digital output bit by bit. The circuitry for bit trials are usually weighted (e.g., binary weighted), and these bit weights are not always ideal. Calibration algorithms can calibrate or correct for non-ideal bit weights and usually prefer these bit weights to be signal-independent so that the bit weights can be measured and calibrated/corrected easily. Embodiments disclosed herein relate to a unique circuit design of an SAR ADC, where each bit capacitor or pair of bit capacitors (in a differential design) has a corresponding dedicated on-chip reference capacitor. The speed of the resulting ADC is fast due to the on-chip reference capacitors (offering fast reference settling times), while errors associated with non-ideal bit weights of the SAR ADC are signal-independent (can be easily measured and corrected/calibrated).

Abstract: Sensor error detection with an additional sensing channel is disclosed herein. First, second, third sensing elements can be disposed at angles relative to one another. In some embodiments, the first, second, and third sensing elements can be magnetic sensing elements, such as anisotropic magnetoresistance (AMR) sensing elements. Sensor data from first, second, and third sensing channels, respectively having the first, second, and third sensing elements, can be obtained. Expected third sensing channel data can be determined and compared to the obtained third sensing channel data to indicate error.

Abstract: The present disclosure relates generally to improving audio processing using an intelligent microphone and, more particularly, to techniques for processing audio received at a microphone with integrated analog-to-digital conversion, digital signal processing, acoustic source separation, and for further processing by a speech recognition system. Embodiments of the present disclosure include intelligent microphone systems designed to collect and process high-quality audio input efficiently. Systems and method for audio processing using an intelligent microphone include an integrated package with one or more microphones, analog-to-digital converters (ADCs), digital signal processors (DSPs), source separation modules, memory, and automatic speech recognition. Systems and methods are also provided for audio processing using an intelligent microphone that includes a microphone array and uses a preprogrammed audio beamformer calibrated to the included microphone array.

Abstract: A receiver system for an on-off key (“OOK”) isolator system may include a receiver that generates an intermediate current signal based on an OOK input signal. The intermediate current may be provided at a first current level when the input signal has a first OOK state and a second current level when the input signal has a second OOK state. The system also may include an output driver to generate a voltage representation of the intermediate current signal. Performing signal processing in a current domain permits fast transitions between OOK states.

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: Embodiments of the present disclosure relate to various methods and example systems for carrying out analog-to-digital conversion of data acquired by arrays of nanogap sensors. The nanogap sensors described herein may operate as molecular sensors to help identify chemical species through electrical measurements using at least a pair of electrodes separated by a nanogap. In general, the methods and systems proposed herein rely on digitizing the signal as the signal is being integrated, and then integrating the digitized results. With such methods, the higher sample rate used in the digitizer reduces the charge per quantization and, therefore, the size of sampling capacitors used. Consequently, sampling capacitors may be made factors of magnitude smaller, requiring less valuable space on a chip compared to sampling capacitors used in conventional nanogap sensor arrays.

Abstract: An amplifier circuit can include an amplifier and a resistor network coupled to the amplifier. The resistor network can include a range resistor coupled in parallel to a resistor string, and one or more switches coupled to the resistor string. The resistor network can be used to calibrate gain and common mode rejection ratio (CMRR) of the amplifier circuit.

Abstract: A microelectromechanical system (MEMS) accelerometer is described. The MEMS accelerometer is arranged to limit distortions in the detection signal caused by displacement of the anchor(s) connecting the MEMS accelerometer to the underlying substrate. The MEMS accelerometer may include masses arranged to move in opposite directions in response to an acceleration of the MEMS accelerometer, and to move in the same direction in response to displacement of the anchor(s). The masses may, for example, be hingedly coupled to a beam in a teeter-totter configuration. Motion of the masses in response to acceleration and anchor displacement may be detected using capacitive sensors.