Abstract: An apparatus includes a charge transfer circuit, a control circuit, and a processing circuit. The charge transfer circuit has a first terminal, a second terminal, a third terminal, and a control input. The control circuit has a control output coupled to the control input. The processing circuit has a first input, a second input, and an output. The processing circuit is configured to receive a first signal at the first input and receive a second signal at the second input. The first signal represents a current through the charge transfer circuit. The second signal represents at least one of a first voltage between the first and second terminals or a second voltage between the second and third terminals. The processing circuit is also configured to provide a third signal based on the first and second signals at the output.

Abstract: A battery system includes a first battery pack having a first positive terminal and a first negative terminal and having a second battery pack having a second positive terminal and a second negative terminal. The second negative terminal is coupled to the first negative terminal. A charge transfer circuit has first, second, and third circuit terminals. The first circuit terminal is coupled to the first positive terminal. The second circuit terminal is coupled to the second positive terminal. The third circuit terminal is coupled to first and second negative terminals.

Abstract: An apparatus comprises a calibration device; a device under test (DUT) connected in series with the calibration device; an electrical interface coupled to the calibration device; a voltage measurement circuit coupled to the electrical interface; a current measurement circuit coupled to the electrical interface; an impedance computation circuit configured to: generate a first impedance of the calibration device in the frequency domain based on first outputs of the voltage measurement circuit and of the current measurement circuit and generate a second impedance of the DUT in the frequency domain based on second outputs of the voltage measurement circuit and of the current measurement circuit; a correction circuit configured to generate parameters representing a correction function based on the first impedance and a reference frequency response of the calibration device and provide a third impedance of the DUT based on combining the parameters with the second impedance.

Abstract: An apparatus includes: a driver circuit having a driver output, the driver circuit including a pulse width modulation (PWM) circuit configured to provide a PWM signal at the driver output at a frequency; a sensing circuit having a sense input and a sense output; and a processing circuit having a processing input and a processing output, the processing input coupled to the sense output, the processing circuit including a filter having zeros at the frequency and multiples of the frequency.

Abstract: An apparatus includes an analog-to-digital converter (ADC) circuit having an analog input, and a digital output, the ADC circuit configured to sample a first signal at the analog input at a sampling frequency and provide a second signal representing samples of the first signal at the digital output. The apparatus further includes a processing circuit having a processing input, a frequency bin width input, a frequency bin index input, and a processing output, the processing input coupled to the digital output, and the processing circuit configured to provide a third signal as a Fourier transform representation of at least a part of the samples at the processing output based on states of the frequency bin width input and the frequency bin index input.

Abstract: A device includes a communication interface, a command processing circuit, a clock synchronization circuit, and a controllable clock source. The command processing circuit has a command input, a reference frequency output, and a reference phase output. The command input is coupled to the communication interface. The clock synchronization circuit has a reference frequency input, a reference phase input, and a frequency control output. The reference frequency output is coupled to the reference frequency input, and the reference phase input coupled to the reference phase output. The clock synchronization circuit includes a frequency synchronization circuit and a phase synchronization circuit. The controllable clock source has a frequency control input and a clock output. The frequency control input is coupled to the frequency control output.

Abstract: An apparatus includes a charge transfer circuit, a control circuit, and a processing circuit. The charge transfer circuit has a first terminal, a second terminal, a third terminal, and a control input. The control circuit has a control output coupled to the control input. The processing circuit has a first input, a second input, and an output. The processing circuit is configured to receive a first signal at the first input and receive a second signal at the second input. The first signal represents a current through the charge transfer circuit. The second signal represents at least one of a first voltage between the first and second terminals or a second voltage between the second and third terminals. The processing circuit is also configured to provide a third signal based on the first and second signals at the output.

Abstract: An apparatus includes a measurement circuit, a high-pass filter circuit, and a processing circuit. The measurement circuit is configured to receive an electrical signal of a device under test (DUT) and generate a measurement signal representing the electrical signal. The high-pass filter circuit is configured to perform a high-pass filtering operation on the electrical signal or the measurement signal to generate a filtered measurement signal. The processing circuit is configured to generate a measurement spectrum of the DUT based on the filtered measurement signal.

Abstract: A system for monitoring one or more physiological parameters includes a plurality of patches positionable at a plurality of locations on a surface of a body, wherein the plurality of patches are electrically isolated from each other, wherein a first patch of the plurality of patches includes a transmitter configured to inject an electrical signal into the body at a first location on the surface of the body, and wherein a second patch of the plurality of patches includes a sensor configured to detect a bio-impedance signal at a second location on the surface of the body that is spaced from the first location, and wherein the bio-impedance signal is induced within the body by the electrical signal injected from the first patch which is electrically isolated from the second patch.

Abstract: A method of non-invasive, continuous, real-time measurement of blood pressure includes applying a wearable blood-pressure monitoring device to a bodily region of a wearer. The wearable blood-pressure monitoring device includes a plurality of pulse sensors or a sensor offering a plurality of observations. The wearable blood-pressure monitoring device is calibrated such that a subset of the plurality of pulse sensors or observations are selected. The selected subset of the plurality of pulse sensors measure a pulse wave velocity and other important physiological parameters of the wearer. The measured pulse wave velocity and other important physiological parameters are converted to a blood pressure of the wearer.