Efficient Power Conversion Corporation

David C Reusch

Michael Andrew De Rooij

Johan Tjeerd Strydom

Jianjun Cao

John Stanley Glaser

Alexander Lidow

Suvankar Biswas

An integrated circuit that includes a plurality of GaN transistor sets. A first set of the plurality of GaN transistor sets includes transistors with a first drain-to-source distance, and wherein a second of the plurality of GaN transistor sets includes transistors with a second drain-to-source distance that is greater than the first drain-to-source distance.

Integrated circuit with multiple gallium nitride transistor sets

A cascaded synchronous bootstrap supply circuit with reduced voltage drop between the cascaded bootstrap capacitors by replacing bootstrap diodes with gallium nitride (GaN) transistors. GaN transistors have a much lower forward voltage drop than diodes, thus providing a cascaded gate driver bootstrap supply circuit with a reduced drop in bootstrap capacitor voltage, which is particularly important as the number of levels increases.

Low voltage drop cascaded synchronous bootstrap supply circuit

An integrated DC-DC converter device includes a plurality of GaN transistor sets. A first set of the plurality of GaN transistor sets includes transistors with a first drain-to-source distance, and wherein a second of the plurality of GaN transistor sets includes transistors with a second drain-to-source distance that is greater than the first drain-to-source distance.

Integrated gallium nitride based DC-DC converter

A drive circuit for a half bridge transistor circuit formed of enhancement mode GaN transistors. A shunt diode is connected to the bootstrap capacitor at a node between the bootstrap capacitor and ground, the shunt diode being decoupled from the midpoint node of the half bridge by a shunt resistor. The shunt diode advantageously provides a low voltage drop path to charge the bootstrap capacitor during the dead-time charging period when both the high side and low side transistors of the half bridge are off.

Bootstrap capacitor over-voltage management circuit for GaN transistor based power converters

A fully integrated GaN driver comprising a digital logic signal inverter, a level shifter circuit, a UVLO circuit, an output buffer stage, and (optionally) a FET to be driven, all integrated in a single package. The level shifter circuit converts a ground reference 0-5 V digital signal at the input to a 0-10 V digital signal at the output. The output drive circuitry includes a high side GaN FET that is inverted compared to the low side GaN FET. The inverted high side GaN FET allows switch operation, rather than a source follower topology, thus providing a digital voltage to control the main FET being driven by the circuit.

Enhancement mode FET gate driver IC

A circuit for an RF switch using FET transistors that largely cancels the non-linearity of the Cof the FETs over a majority of the signal range, and reduces distortion. The RF switch includes two substantially identical FETs. The source of one FET is connected to the drain of the other FET and the node formed comprises one terminal of the switch. Two substantially identical capacitors are connected in series with each other and in parallel with the FETs, and the node thus formed comprises the second terminal of the switch. The capacitors are selected such that they have negligible impedance at AC frequencies for which the switch is expected be used, and in particular a much lower impedance than Cof each FET. A voltage source with a series impedance is also connected in parallel with the capacitors and the two FETs.

Low distortion RF switch

An electrical circuit arranged in a half bridge topology. The electrical circuit includes a high side transistor; a low side transistor; a gate driver and level shifter electrically coupled to a gate of the high side transistor; a gate driver electrically coupled to a gate of the low side transistor; a capacitor electrically coupled in parallel with the gate driver and level shifter; a voltage source electrically coupled to an input of the gate driver and level shifter and an input of the gate driver; and, a bootstrap transistor electrically coupled between the voltage source and the capacitor. A GaN field-effect transistor is synchronously switched with a low side device of the half bridge circuit.

High voltage zero QRR bootstrap supply

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A highly efficient, single sided circuit board layout design providing magnetic field self-cancellation and reduced parasitic inductance independent of board thickness. The low profile power loop extends through active and passive devices on the top layer of the circuit board, with vias connecting the power loop to a return path in an inner layer of the board. The magnetic effect of the portion of the power loop on the top layer is reduced by locating the inner layer return path directly underneath the power loop path on the top layer.

Growing community of inventors

Blacksburg, VA, United States of America

David C Reusch