Linear Technology Corporation

Linear Technology Holding LLC

Analog Devices,inc.

Analog Devices International Unlimited Company

Mark Robert Vitunic

Eko Lisuwandi

Samuel Hodson Nork

Steven Leo Martin

Edward Lloyd Henderson

Jinhuang Lu

Samuel H Nork

For inductor-based DC-DC converters, a current shunt switch can provide an alternate path for the inductor current to flow that does not include the output capacitor. An amplifier circuit can be included and coupled with a control node of the current shunt switch to adjust a voltage on the control node to control an amount of inductor current diverted away from the output node. A fast linear loop can be included to ensure smooth transitions when engaging or disengaging the current shunt switch. These techniques can minimize the amount and duration of the subsequent negative output voltage excursion, which can be dependent on the specific ESL and ESR values of the output voltage capacitor, for the cases when the final value of the step-down load-transient is not zero. These techniques can improve a positive output voltage response caused by an output load transient in the negative direction.

Techniques for linear control of inductor current shunt for mitigation of load dump transients in DC-DC regulators

A voltage regulator circuit comprises a switching circuit configured to adjust a switching duty cycle to regulate an output voltage at an output node of the voltage regulator circuit using an error signal representative of a difference between a target voltage value and the output voltage; an inductor coupled to the switching circuit and configured to provide an inductor current to the output node; and a shunt circuit coupled in parallel to the inductor and configured to divert the inductor current away from the output node when the output voltage exceeds a specified maximum output voltage.

Inductor current shunt for mitigation of load dump transients in DC-DC regulators

A wireless power transfer system may wirelessly transmit and receive power. A transmitting coil may wirelessly transmit the power. A receiving coil may be magnetically but wirelessly coupled to the transmitting coil and may wirelessly receive the power and generate an AC input voltage. A rectifier may rectify the AC input voltage. A capacitance may filter the rectified AC input voltage. An electronic switch may be connected in series between the rectified AC input voltage and an output. A load may be connected to the output. A controller may open and close the electronic switch so as to cause the output to be at a constant DC voltage, notwithstanding variations in the load.

Open circuit-based Rx power limiter for wireless power transfer

A method and system of counting coulombs drawn from a power source by a load. A reference current source regulates the current drawn by the load at any given time to be either zero or a predetermined fixed amount. A comparator controls a time the switch is closed and open. When the switch is closed, coulombs are allowed to be drawn from the power source, and prevented to be drawn when the switch is open. An oscillator generates a clock signal during the time the switch is closed. A counter counts the number of clock cycles from the clock signal during the time the switch is closed. The count is provided as a signal at a second output of the coulomb counter.

Input current conditioner for precision coulomb counting

Novel circuitry and methodology are provided for correcting the offset associated with a voltage-controlled current source. An offset correction circuit is coupled to the current source to prevent the output current produced by the current source from deviating from a desired level. The current source may include a transconductance amplifier or a chopper amplifier, and may be configured to produce a zero or non-zero value of the output current.

Offset correction circuit for voltage-controlled current source

A battery balancing system includes at least one sub-stack, each sub-stack comprising a plurality of cells connected in series. The system also includes a balancing module for each sub-stack comprising an independent bidirectional balancer for each cell in the sub-stack. The system includes a daisy chained stackable serial port. The balancing system senses a state of charge (SOC) of each cell in each sub-stack. The average SOC of the sub-stack is determined. For a weak cell, additional charge is provided from its respective sub-stack during the discharging of the battery. For a strong cell, additional charge is removed and provided to its respective sub-stack during discharging of the battery. Any number of sub-stacks can be stacked in series while maintaining the same serial control, allowing a theoretically unlimited number of cells to be supported from a single communication port without the need for additional digital isolators.

Stackable bi-directional multicell battery balancer

High efficiency drive circuitry for a group of parallel-connected light emitting devices, in which each device is driven in series by a respective source of bias current. The maximum voltage drop among the group of biased light emitting devices is determined and in response, a control voltage to drive all the light emitting device at the lowest effective voltage for the LED group is produced.

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Lexington, MA, United States of America

Mark Robert Vitunic