Virginia Tech Intellectual Properties, Inc.

Toyota Motor Engineering & Manufacturing North America, Inc.

Zichen Miao

Khai Ngo

Chi-Ming Wang

Yincan Mao

Lujie Zhang

A power circuit includes a power source for providing electrical power and two driving transistors being disposed in parallel and receiving electrical power from the power source. Each of the two driving transistors includes a gate terminal, a source connection, and a kelvin source connection. The power circuit also includes a control voltage source having a first terminal and a second terminal. The control voltage source provides a control signal to the two driving transistors for determining driving currents through the two driving transistors. The first terminal is connected to the gate terminals of the two driving transistors, and the second terminal is connected to the kelvin source connections of the two driving transistors. The kelvin source connections of the two driving transistors are inductively coupled.

Parallel devices having balanced switching current and power

Capacitors connected between gate terminals of a plurality of parallel-connected power transistors are charged and discharged in each switching cycle to provide a plurality of power transistor control waveforms from a single gate driver waveform that equalize power losses/temperatures or steady-state currents among the plurality of power transistors. The capacitors are charged to different voltages by diverting current from one transistor driver by disabling another power transistor driver at different respective times in response to measured transient or steady state current or temperature or other operational parameter.

Power switch drivers with equalizers for paralleled switches

Aspects of the disclosure provide a system having a power circuit. The power circuit includes a first switch circuit having at least a first transistor and a second switch circuit having at least a second transistor. Further, the power circuit includes first interconnections configured to couple the first switch circuit to driving nodes, a source node and a drain node of the power circuit, and second interconnection configured to couple the second switch circuit in parallel to the first switch circuit to the driving nodes, the source node and the drain node of the power circuit. A polarity of unbalance in the first interconnections and the second interconnections dominates a polarity of current unbalance in the first switch circuit and the second switch circuit.

Method and apparatus for current/power balancing

Aspects of the disclosure provide a power device that includes an upper power module and a lower power module. The upper power module and the lower power module are coupled in series between two supply voltages, and are respectively controlled by a first control signal and a second control signal. Interconnections of the power device are inductively coupled to prevent reliability issues, such as crosstalk, self turn on, self sustained oscillation, and the like.

Method and apparatus to improve power device reliability

Aspects of the disclosure provide a power circuit that includes a first switch circuit in parallel with a second switch circuit. The first switch circuit and the second switch circuit are coupled to a first driving node, a second driving node, a source node and a drain node via interconnections. The power circuit receives a control signal between the first driving node and the second driving node to control a current flowing from the drain node to the source node through the first switch circuit and the second switch circuit. In the power circuit, a first interconnection and a second interconnection of the interconnections are inductively coupled to balance the current flowing through the first switch circuit and the second switch circuit.

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Blacksburg, VA, United States of America

Zichen Miao