Cirrus Logic Inc.

Rfmicron, Inc.

Other

Vitesse Semiconductor Corporation

Cicada Semiconductor Corporation

Koninklijke Philips Corporation N.v.

Crystal Semiconductor Corporation

John James Paulos

Shahriar Rokhsaz

John L Melanson

Ahmed Younis

Marwan M Hassoun

Brian David Young

Andrew W Krone

Jason Powell Rhode

Abhay Misra

Benjamin Cooke

Gautham Devendra Kamath

Prashanth Drakshapalli

Nicholas R Van Bavel

Eric Clay Gaalaas

Guanghui Hu

Martin Gutierrez

Eric James Wyers

Richard Bocock

Vishnu Shankar Srinivasan

John Christopher Tucker

Eric Kimball

Edmund Mark Schneider

Dylan Alexander Hester

Xue-Mei Gong

Karl Ernesto Thompson

Kartik Nanda

Larry L Harris

Magesh Valliappan

Mauro L Gaetano

Scott T Dupuie

James Francis McElwee

Mark Alexander

Thirumalai Rengachari

James Martin Nohrden

John Robert Pacourek

Dan Stiurca

Ram Krishnamurthy

Lei Jin

A radio frequency identification (RFID) tag includes an antenna, an analog front end, a processing circuit, and memory. The analog front end includes a power circuit, a tuning circuit, a transmitter, and a receiver. The power circuit is operably coupled to convert a radio frequency (RF) signal into a power supply voltage. The tuning circuit, when enabled, adjusts an RF characteristic of the analog front end to tune power harvesting from the RF signal. The transmitter is operably coupled to transmit a response signal to the RFID reader via the antenna. The receiver is operably coupled to receive a command signal from the RFID reader, wherein the command signal is contained within a portion of the RF signal. The processing circuit is operable to interpret the command signal and generate the response signal.

Pressure based wireless sensor and applications thereof

A method includes processing, by a processing module of a data logging device, a plurality of log commands. The processing of a log command of the plurality of log commands includes obtaining a measure of an environmental condition. The processing further includes updating a status of the environmental condition based on the measure of an environmental condition. The method further includes determining, by the processing module, the updated status of the environmental condition after the plurality of log commands have been processed. When the updated status of the environmental condition is favorable, the method further includes generating, by the processing module, a favorable environmental condition signal.

Data logging with pass indication

A method includes establishing, by a data logging device, a sleep mode. The method further includes receiving, by a processing module of the data logging device, a second activation command that causes the data logging device to transition to a standby mode. The method further includes receiving, by the processing module, a third activation command that causes the data logging device to transition to a ready mode. The method further includes receiving, by the processing module, a fourth activation command that causes the data logging device to transition to a logging mode. In the logging mode, the method further includes obtaining, by the processing module, a log command. In response to the log command, the method further includes obtaining, by the processing module, a measure of an environmental condition. The method further includes storing the measure of the environmental condition in memory of the data logging device.

Method and apparatus of data logging

An improved AC-to-DC charge pump for use, for example, in voltage generation circuits. In one embodiment, two 2-diode charge pumps are coupled in back-to-back configuration, and adapted to develop a substantially stable voltage on a mid-level rail. In one other embodiment, two 3-diode charge pumps are coupled in back-to-back configuration, and adapted also to develop a substantially stable voltage on a mid-level rail. In one preferred embodiment, all diodes are implemented as current-source-biased MOSFETs.

AC-to-DC charge pump having a charge pump and complimentary charge pump

A method begins by a first radio frequency identification (RFID) sensor, that is associated with a first object element, receiving a first data request signal from an RFID reader and sending a first radio frequency (RF) signal that includes first data to the RFID reader in response to the first data request signal. The method continues with a second RFID sensor receiving a second data request signal from, and sending second data to, the RFID reader. The method continues with the RFID reader sending a representation of the first and second data to a data processing unit, which processes the representation of the first and second data to determine a first and second data point regarding first and second object elements. The method continues by the data processing unit processing the first and second data points to determine an environmental relationship between the first and second object elements.

Radio frequency identification (RFID) tag(s) and sensor(s)

A wireless sensor includes an antenna, a sensing element, a tuning circuit, a processing module, a reference circuit block, and a transmitter. The tuning circuit adjusts the RF front-end to compensation for a change in a characteristic of the RF front end caused by the sensing element. The reference circuit block generates a signal based on a low voltage low frequency input that corresponds to a second environmental condition. The processing module generates a first digital value based on the adjustment to the RF front-end, where the first digital value is a representation of the first environmental condition, and generate a second digital value based on the signal, where the second digital value is a representation of the second environmental condition. The transmitter generates the outbound RF signal that includes at least one of the first and second digital values.

A passive radio frequency identification (RFID) sensor is provided. This passive RFID sensor includes at least one antenna, at least one processing module, and a wireless communication module. The at least one antenna has an impedance that may vary with an environment in which the sensor is placed. Additionally, the antenna impedance might be permanently changed in response to an environmental variation or an event. The at least one processing module couples to the antenna and has a tuning module that may vary a reactive component impedance coupled to the antenna in order to change a system impedance. The system impedance includes both the antenna impedance and the reactive component impedance. The tuning module then produces an impedance value representative of the reactive component impedance. A memory module may store the impedance value which may then later be communicated to an RFID reader via the wireless communication module. The RFID reader may then exchange the impedance value representative of the reactive components of impedance with the RFID reader such that the RFID reader or another external processing unit may process the impedance value in order to determine environmental conditions at the inductive loop. These environmental conditions may include but are not limited to temperature, humidity, wetness, or proximity of the RFID reader to the passive RFID sensor.

A system and method map dimming levels of a lighting dimmer to light source control signals using a predetermined lighting output function. The dimmer generates a dimmer output signal value. At any particular period of time, the dimmer output signal value represents one of multiple dimming levels. In at least one embodiment, the lighting output function maps the dimmer output signal value to a dimming value different than the dimming level represented by the dimmer output signal value. The lighting output function converts a dimmer output signal values corresponding to measured light levels to perception based light levels. A light source driver operates a light source in accordance with the predetermined lighting output function. The system and method can include a filter to modify at least a set of the dimmer output signal values prior to mapping the dimmer output signal values to a new dimming level.

Lighting system with lighting dimmer output mapping

A system and method modify phase delays of a periodic, phase modulated mains voltage to generate at least two independent items of information during each cycle of the periodic input signal. The independent items of information can be generated by, for example, independently modifying leading edge and trailing edge phase delays of each half cycle phase modulated mains voltage. Modifying phase delays for the leading and trailing edges of each half cycle of the phase modulated mains voltage can generate up to four independent items of data. The items of data can be converted into independent control signals to, for example, control drive currents to respective output devices such as light sources to provide multiple items of information per cycle.

Multi-function duty cycle modifier

A power control system and method senses input and/or output voltages of a power supply using sense currents in order for an integrated circuit (IC) switch state controller to generate a control signal to control a switch of the power control system. By sensing sense currents, the power control system can eliminate at least one sense resistor used in a voltage sense system. The sense current(s) can be used to provide power and sensing to the switch state controller. In at least one embodiment, the sense current(s) provide power to the switch state controller when auxiliary IC power is unavailable or diminished, such as during start-up of the IC. In at least one embodiment, the IC draws more sense current from an input of the power control system than the output of the power control system to, for example, minimize impact on the output voltage of the power supply.

Powering a power supply integrated circuit with sense current

A temperature and process-stable magnetic field sensor bias current source provides improved performance in Hall effect sensor circuits. A switched-capacitor sensing element is used to sense either a reference current or the bias current directly. A current mirror may be used to generate the bias current from the reference current, and may include multiple current source transistors coupled through corresponding control transistors that are switched using a barrel shifter to reduce variations in the bias current due to process variation. The current mirror control may be provided via a chopper amplifier to reduce flicker noise and the current mirror control voltage may be held using a track/hold circuit during transitions of the chopper amplifier to further reduce noise due to the chopping action.

Temperature and process-stable magnetic field sensor bias current source

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Austin, TX, United States of America

John James Paulos