Linear Technology Corporation

Analog Devices International Unlimited Company

Other

Fidelica, Microsystems, Inc.

Optoceutics Aps

Robert C Dobkin

Carl T Nelson

Robert Loren Reay

Thomas P Hack

Dennis P O'Neill

Steven M Pietkiewicz

Brendan John Whelan

Albert M Wu

Shiva Prakash

Milton E Wilcox

William C Rempfer

Srinivasan K Ganapathi

Randolph S Gluck

John W Wright

Keith T Deconde

Amitkumar Pravin Patel

Jeffrey Schenkel

Yuhui Chen

Steve Hovey

Surapap Rayanakorn

James Vincent Sousae

Aref Kahaei

Jonathan Noah Simon

David McLean Dwelley

Mark Alan Lemkin

Barry G Broome

Lance Robert Doherty

Thor Juneau

Randy Guy Flatness

Chiawei Liao

Jes Broeng

Michael B Anderson

Joseph Gerard Petrofsky

Nello George Sevastopoulos

Robert Essaff

Robert Chiacchia

Alain Pierre Levesque

Brett Warneke

Wadie N Khadder

Gordon Alexander Charles

Andrew Bishop

David Roy Ng

David Henry Soo

Bernhard Helmut Engl

Doug Allen LaPorte

George F Feliz

George Erdi

Samuel Patrick Rankin

Xigen Zhou

Erik Soule

James P Vokac

Ngoc Mai Nguyen

Mark Henney

Paul Michael Petersen

Marcus Carstensen

Alfonso Centuori

Denes E Frankel

Chong K Lai

Michael Brian Anderson

An integrated circuit (IC) heater circuit comprises a drive circuit configured to increase the temperature of the IC when consuming power; a temperature sensor coupled to a control node of the drive circuit to activate and deactivate the drive circuit to provide an ambient temperature for the IC, wherein current of the temperature sensor varies with temperature; and a control circuit coupled to the temperature sensor and configured to adjust variation in the temperature sensitivity of the current of the temperature sensor.

Bipolar junction transistor heater circuit

Gamma brain stimulation for preventing or treating Alzheimer's disease or sleeping disorders using light or sound is known. A strobing 40 Hz light source has been shown to cause positive effects due to the stimulation. It is an advantage to know the actual dosage of light that enters the person's eyes in order to understand the relationship between dosage and effectiveness. A camera is used to detect the subject's gaze angle, distance, pupil diameter and any other factors that affect the light power that enters the eye. A target dosage is first determined by a medical worker, such as to determine the effects of the exact same dosage on a group of similar persons, such as Alzheimer's patients. With deviations of gaze angle, distance, and pupil size from the ideal, the effective dosage is decreased. The disclosed system adjusts the actual dosage, such as session duration, based on such factors so that the final dosage received by the person is consistent and meets the target dosage.

Gamma stimulation pulsing light source system with dosage adjustment for gaze angle

A battery system monitor includes cell measurement circuits (CMCs) that each measure a voltage at or current through a pair of terminals of a respective associated battery module from among a plurality of plurality of battery modules in a battery system. Wireless communication transceivers (WCTs), each associated with a different CMC, transmit voltage or current measurement information of the associated CMC across a wireless communication link. A controller receives the voltage or current measurement information from the wireless communication transceivers for monitoring the state of operation of the battery system. Battery system monitoring is improved through synchronization of clocks in different CMCs or WCTs to enable synchronous sampling of multiple battery modules, through systems for determining relative positions of battery modules in a series coupling of battery modules between terminals of the battery system, and through improvements to the reliability of wireless communication.

Wireless sensing for battery systems

A ripple monitoring circuit may generate information indicative of a failing component in a power supply. At least one input may receive a ripple signal from the power supply that has a ripple component. A quantization circuit may repeatedly quantize the amplitude of the ripple component. A ripple amplitude statistics counter bank may count and store the number of times that different quantized amplitudes or different ranges of quantized amplitudes of the ripple component occurred. A ripple monitoring circuit may generate information about a power supply. At least one input may receive a ripple signal from the power supply that has a ripple component. A ripple measurement circuit may measure a characteristic of the ripple component. A storage circuit may store information about the measurement. A comparison circuit may compare information stored in the storage circuit with a threshold value and indicate when the stored information meets or exceeds this threshold value.

Ripple monitoring

In one embodiment, a regulator circuit for generating a regulated output voltage Vout has an error amplifier using a pair of bipolar transistors at its front end. The error amplifier compares the regulated output voltage to a reference voltage Vref. A precision current source draws a first current through a user-selected set resistance to generate the desired Vref. The regulator circuit controls a power stage to cause Vout to be equal to Vref. The base current into one of the bipolar transistors normally distorts the current through the set resistance. A base current compensation circuit is coupled to the current source to adjust the first current by a value equal to the base current to offset the base current. Therefore, Vref is not affected by the base current. The error amplifier may be in a linear regulator or a switching regulator. The compensation circuit may be used in other applications.

Voltage generator with current source compensated for an error current operable over a wide voltage range

A linear regulator integrated circuit may be formed having four external terminals including a voltage input (Vin) terminal, a voltage output (Vout) terminal, a Set terminal, and an operational amplifier (op amp) power terminal. A user connects an external resistor to the Set terminal for creating a reference voltage. An op amp controls a pass (or series transistor) to cause an output voltage at the Vout terminal to equal the reference voltage. The op amp has a first power supply terminal internally coupled to the Vin terminal and a second power supply terminal coupled to the op amp power terminal. The op amp power terminal allows a user to externally couple the op amp second power supply terminal to either the Vout pin (for high voltage applications), system ground (for medium voltage applications), or another voltage (to provide additional headroom in very low voltage applications).

Linear regulator IC with versatile ground pin

An automatic voltage compensation circuit in a voltage regulator compensates the output voltage for a voltage drop along lines leading to a remote load. A load capacitor is connected across the load for providing a low impedance across the load during a test phase of the regulator. In one embodiment, during the test phase, the load current is changed up or down a small percentage (e.g., 10%). As a result, the regulator voltage changes due only to the line resistance since the load is bypassed by the load capacitor. The voltage drop at full load current is then derived by detecting the change in regulator output voltage (a fractional voltage drop) and multiplying it. The normal mode is resumed, and the derived voltage drop is added to the regulator output by either compensating the feedback loop or by adding the voltage drop to the output of the regulator.

Voltage regulator compensating for voltage drop along conductors between regulator output and load

An overvoltage protection method and circuit includes a positive supply input node, an output node, and a negative supply node. The overvoltage protection circuit further includes a first functional circuit configured to turn ON a MOSFET and maintain it in a low resistance state. A second functional circuit is configured to detect an overvoltage and control the gate of the MOSFET to regulate a voltage at the output node. A third functional circuit is configured to provide a startup wherein the overvoltage protection circuit is not damaged and/or to regulate an operating voltage such that an overvoltage does not appear on the overvoltage protection circuit. The external components include the MOSFET, which has a gate coupled to the output of the charge pump of the overvoltage protection circuit.

Circuitry to prevent overvoltage of circuit systems

Circuits and methods for paralleling voltage regulators are provided. Improved current sharing and regulation characteristics are obtained by coupling control terminals of the voltage regulators together which results in precise output voltages and proportional current production. Distributing current generation among multiple paralleled voltage regulators improves heat dissipation and thereby reduces the likelihood that the current produced by the voltage regulators will be temperature limited.

Paralleling voltage regulators

A clamping circuit clamps a voltage received by an n-type semiconductor region without using a Schottky transistor. The clamping circuit includes a current mirror as well as first and second bipolar transistors. The current mirror receives a first current and supplies a second current in response. The first current is received by the first bipolar transistor, and the second current is received by the second bipolar transistor. The difference between the base-emitter junction voltages of the first and second bipolar transistors, in part, defines the voltage at which the n-type region is clamped. To start-up the circuit properly, current is withdrawn from the base/gate terminals of the transistors disposed in the current mirror. The circuit optionally includes a pair of cross-coupled transistors to reduce the output impedance and improve the power supply rejection ratio.

Method for clamping a semiconductor region at or near ground

Circuits and methods that improve the performance of reference circuits are provided. A reference generator circuit maintains a substantially constant output current over an extended temperature for use as a reference. Output current fluctuations caused by a poorly specified power source or process variations are minimized or eliminated.

Bandgap voltage and current reference

Apparatus is configured for producing an output signal indicating an operating status of a monitored circuit. An input signal relating to the monitored circuit is received at an input node. A pulse train generator, coupled to the input node, is configured for generating a pulse train of a prescribed repetition rate at a duty cycle alternated between first and second duty cycle values at a prescribed frequency. The duty cycle and frequency are indicative of operating status of the monitored circuit.

Apparatus and method for producing signal conveying circuit status information

A first and a second group of individual transistors in a voltage reference may collectively function as a first and a second composite transistor with a first and a second emitter area equal to the combined areas of the emitters of the first and the second groups of individual transistors, respectively. The second emitter area may be larger than the first emitter area. The stability of the reference voltage may depend upon the stability of the ratio between the first emitter area and the second emitter area. The first group of individual transistors may not be at the center of an arrangement of the second group of individual transistors. The constant reference voltage may vary due to thermal hysteresis by less than 200 parts per million over a 40 degree centigrade temperature range.

Low thermal hysteresis bandgap voltage reference

Growing community of inventors

Monte Sereno, CA, United States of America

Robert C Dobkin