Nonin Medical, Inc.

Polar Semiconductor, Inc.

Gregory J Rausch

Michael J Gaboury

Shohei Osaka

Matthew Prior

Timothy L Johnson

Robert John Schuelke

Aaron Alfred Lobbestael

David Lee Lemke

Marcus A Kramer

Nicholas J Kanavati

Hugh Ferguson

Scott Gregory Klimek

A system includes a garment and a sensor module. The garment includes an engagement feature. The garment is configured to encompass a first location on a body. The engagement feature is positioned in fixed alignment with the garment. The sensor module includes a sensor housing and includes a sensor having an electrical node. The sensor is configured to provide an electrical output on the node. The housing has a complementary feature. The complementary feature is configured to couple and decouple with the engagement feature. The electrical output is based on a measure of a physiological parameter associated with the body and is based on site information corresponding to the engagement feature.

Tissue interface

A method includes affixing a co-planar sensor on a surface, using a processor, and providing an output. The method includes affixing a co-planar sensor on a surface at a first tissue site. The sensor has a force transducer disposed at an aperture of a rigid guard member. The guard member and the transducer are in co-planar alignment. The transducer is configured to provide an electrical signal corresponding to an internal pressure at the first tissue site. The method includes using the processor to compare the internal pressure with a reference value. Based on the comparison, the method includes providing an output corresponding to compartment syndrome at the first tissue site.

Noninvasive pressure monitoring

A device includes a housing, an emitter, a detector, and a processor. The housing has a body contact surface. The emitter is coupled to the housing and has an emission surface and has an electrical terminal. The emission surface is configured to emit light proximate the body contact surface in response to a signal applied to the electrical terminal. The detector is coupled to the housing. The detector has a sense surface and an output terminal. The detector is configured to provide an output signal on the output terminal in response to light detected at the sensor surface. The processor is configured to implement an algorithm to determine a tissue site based on the emitted light and based on the detected light.

Tissue site detection

A device includes a housing, an emitter, a detector, and a processor. The housing has a body contact surface configured for affixation to a tissue site of a body. The emitter is coupled to the housing and has an emission surface and an electrical terminal. The emission surface is configured to emit light proximate the body contact surface in response to a signal applied to the electrical terminal. The detector is coupled to the housing. The detector has a sense surface and an output terminal. The detector is configured to provide an output signal on the output terminal in response to light detected at the sensor surface. The processor is coupled to the electrical terminal and coupled to the output terminal. The processor is configured to implement an algorithm to monitor for an interruption between the body contact surface and the body and configured to generate an interrupt signal corresponding to the monitoring.

Interrupt detection for physiological sensor

A device includes a digit probe, a plurality of optical elements, a processor, and a communication module. The digit probe has an interior surface and has an exterior surface. The interior surface is configured to engage a digit and the exterior surface is configured to engage a tissue site associated with the digit. The plurality of optical elements is coupled to at least one of the interior surface and the exterior surface. The plurality of optical elements includes at least one emitter and includes at least one detector. The processor is coupled to the plurality of optical elements. The processor is configured to generate a measure of arterial oxygenation corresponding to the digit and configured to generate a measure of regional oxygenation corresponding to the tissue site. The communication module is coupled to the processor. The communication module is configured to communicate the measure of arterial oxygenation and regional oxygenation with a remote device.

Universal fingertip sensor

A method of controlling a power factor correction (PFC) converter having a first PFC sub-circuit and a second PFC sub-circuit determines when to transition the PFC converter between an interleaved mode and a saving energy mode (SEM). The method includes generating an amplified error signal based on a monitored output voltage of the PFC converter. The second PFC sub-circuit is disabled in response to the amplified error signal being less than a first threshold value and enabled in response to the amplified error signal exceeding a second threshold value.

Saving energy mode (SEM) for an interleaved power factor correction (PFC) converter

A controller provides frequency compression for an interleaved power factor correction (PFC) converter that determines the ON and OFF times of each switch associated with the PFC converter to prevent operating frequencies in the audible range. The controller includes a first circuit for generating an ON time current source having a magnitude related to an amplified error signal and the monitored input voltage, and a second circuit for generating an OFF time current source having a magnitude related to the ON time current source, the monitored input voltage, and the monitored output voltage. Gate drive circuitry provides gate drives signals to the switches of the interleaved PFC converter at a frequency determined by magnitudes of the ON time current source and the OFF time current source.

Frequency compression for an interleaved power factor correction (PFC) converter

The present invention provides a method of controlling an interleaved power factor correction (PFC) circuit operating in a discontinuous conduction mode (DCM). The controller employs a normal mode of operation in which inductor currents in each PFC sub-circuit are estimated based on the monitored input voltage and monitored output voltage, and switching devices associated with each PFC sub-circuit are controlled to ensure DCM operation. As the input voltage increases, the OFF times of each PFC sub-circuit increase such that the inductor currents no longer overlap. In response, the controller activates a time-limiting mode (TLM) in which OFF time durations for each sub-circuit are based on the monitored sum of load currents as opposed to the monitored input voltage and monitored output voltage.

Time-limiting mode (TLM) for an interleaved power factor correction (PFC) converter

A controller generates a drive signal for a converter circuit that includes an active component (i.e., transistor) that is selectively controlled to convert a rectified input to direct current (DC) output. The controller employs an outer feedback loop (based on monitored output voltage of the converter circuit), an inner feedback loop (based on monitored AC input current drawn by the converter circuit), and a pulse width modulator (PWM) to generate the drive signals necessary to generate the desired DC output voltage and to provide power factor correction to the converter circuit. In particular, the inner feedback loop includes an amplifier and a fault protection and clamp circuit. The amplifier has a first input connected to receive a feedback signal representing the monitored AC input current, a second input, and an output that provides a current feedback signal to the PWM. The fault protection and clamp circuit is connected to monitor the voltage at the second input of the PWM and to detect fault conditions associated with the converter circuit, wherein in response to an over-voltage condition at the second input or a detected fault condition the fault protection and claim circuit clamps the current feedback signal provided to the second input of the PWM to a reference value and provides the reference value in feedback to either the first or second input of the amplifier.

Protection and clamp circuit for power factor correction controller

A current-mode under voltage lockout (UVLO) circuit provides an output signal that indicates to connected devices whether a connected power supply is sufficient (i.e., of sufficient strength and stability) based on a comparison of a current that is proportional to the power supply and a reference current. The current-based UVLO circuit employs a reference current generator that is capable of providing a stable reference current and a voltage-to-current converter that provides a current proportional to the power supply voltage. A comparator compares the reference current to the current proportional to the power supply voltage and determines based on the magnitudes of the two currents whether the power supply voltage is sufficient or 'good' and generates an output signal indicating the status of the power supply voltage.

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Minnetonka, MN, United States of America

Gregory J Rausch