Abstract: GaN-based half bridge power conversion circuits employ control, support and logic functions that are monolithically integrated on the same devices as the power transistors. In some embodiments a low side GaN device communicates through one or more level shift circuits with a high side GaN device. Various embodiments of level shift circuits and their inventive aspects are disclosed.

Abstract: A circuit is disclosed. The circuit includes a transformer having a primary winding extending between a first terminal and a second terminal, and further including a secondary winding extending between a third terminal and a first output terminal; a first switch having a first gate terminal, a first source terminal and a first drain terminal, the first drain terminal coupled to the second terminal and the first source terminal coupled to a power source; a second switch having a second gate terminal, a second source terminal and a second drain terminal, the second source terminal coupled to the second terminal, and the second drain terminal coupled to the power source; and a third switch having a third gate terminal, a third source terminal and a third drain terminal, the third source terminal coupled to the third terminal and the third drain terminal coupled to a second output terminal.

Abstract: Methods of operating a circuit are disclosed. In one aspect, disclosed methods includes providing a power converter circuit having transformer with a primary winding and secondary winding, a first switch and second switch coupled to the primary winding, a third switch coupled to the secondary winding, a controller coupled to the first and second switches. Disclosed methods further includes sensing a turn-on of the third switch and in response, transmitting a turn-on signal to the controller; and turning-on the second switch, using the controller, in response to receiving the turn-on signal. In another aspect, disclosed methods further includes sensing a turn-off of the third switch and in response, transmitting a turn-off signal to the controller using an isolation module, and turning-off the second switch, using the controller, in response to receiving the turn-off signal. In yet another aspect, the second switch is turned-off, using the controller, after a delay time.

Abstract: An electronic device is disclosed. In one aspect, the electronic device includes a printed circuit board (PCB) having a first surface and a second surface opposite the first surface, where the PCB includes a thermally conductive region having a plurality of vias that extend from the first surface to the second surface; a semiconductor device attached to the second surface of the PCB and overlying the thermally conductive region; a transformer having a magnetic core; a shield arranged to partially enclose the transformer and define an opening; and an insert disposed within the opening, attached to the first surface of the PCB and overlying the thermally conductive region.

Abstract: A power converter comprises a chassis and an AC connector, a low-voltage DC connector and a high-voltage DC connector at an exterior surface of the chassis. An AC-DC converter circuit is positioned at least partially within the chassis and is coupled to the AC connector. A first converter circuit is positioned at least partially within the chassis and is coupled to the AC-DC converter circuit and to a high-voltage DC bus. The high-voltage DC bus is connected to the high-voltage DC connector. A second converter circuit is positioned at least partially within the chassis and is coupled to the high-voltage DC bus to a low-voltage DC bus. The low-voltage DC bus is connected to the low-voltage DC connector.

Abstract: Systems and methods for improving radiated electromagnetic interference (EMI) in switching power supplies are disclosed. In one aspect, a converter circuit includes a transformer having a primary winding and a secondary winding, the primary winding extending from a first primary terminal to a second primary terminal, a first switch having a first gate terminal, a first source terminal and a first drain terminal, wherein the first drain terminal is coupled to the first primary terminal, and the first source terminal is coupled to a power source, and a capacitor having a first capacitor terminal and second capacitor terminal, wherein the first capacitor terminal is coupled to the power source. A ferrite bead is coupled between the first primary terminal and the first drain terminal, and a capacitor network is coupled in parallel with the ferrite bead and arranged to reduce radiated electromagnetic interference of the converter circuit.

Abstract: Gallium nitride reference voltage generation circuits. In one aspect, the circuit includes a first gallium nitride (GaN)-based transistor having a first gate terminal, a first source terminal and a first drain terminal, a second GaN-based transistor having a second gate terminal, a second source terminal and a second drain terminal, the second gate terminal coupled to the first drain terminal, an input terminal coupled to the first gate terminal and arranged to receive a first voltage, an output terminal coupled to the second source terminal, a power supply terminal coupled to the first drain terminal and the second drain terminal, and a feedback circuit coupled between the first source terminal and the second source terminal, where the first source terminal is coupled to a ground through a first impedance element, the first impedance element having a positive temperature coefficient.

Abstract: A low power-loss supply circuit minimizes the losses in a synchronous rectifier power conversion circuit by regulating the voltage supply (Vcc) of a synchronous rectifier controller. The low power-loss supply circuit uses two regulating capacitors to regulate the value of the voltage supplied to the controller. A first regulating capacitor supplies the input voltage which powers the synchronous rectifier controller. A second regulating capacitor is used to cyclically charge the first regulating capacitor.

Abstract: GaN-based half bridge power conversion circuits employ control, support and logic functions that are monolithically integrated on the same devices as the power transistors. In some embodiments a low side GaN device communicates through one or more level shift circuits with a high side GaN device. Various embodiments of level shift circuits and their inventive aspects are disclosed.

Abstract: An electronic device includes a semiconductor substrate and a bidirectional transistor switch formed on the substrate, the bidirectional switch including a first source node, a second source node and a common drain node. A first transistor is formed on the substrate and includes a first source terminal, a first drain terminal and a first gate terminal, wherein the first source terminal is connected to the substrate, the first drain terminal is connected to the first source node and the first gate terminal is connected to the second source node. A second transistor is formed on the substrate and includes a second source terminal, a second drain terminal and a second gate terminal, wherein the second source terminal is connected to the substrate, the second drain terminal is connected to the second source node and the second gate terminal is connected to the first source node.

Abstract: GaN-based half bridge power conversion circuits employ control, support and logic functions that are monolithically integrated on the same devices as the power transistors. In some embodiments a low side GaN device communicates through one or more level shift circuits with a high side GaN device. Various embodiments of level shift circuits and their inventive aspects are disclosed.

Abstract: A circuit is disclosed. The circuit includes a first transistor including a first drain terminal, a first gate terminal and a first source terminal, a depletion-mode transistor including a second drain terminal, a second gate terminal and a second source terminal, the second drain terminal connected to the first drain terminal, the depletion-mode transistor arranged to sense a first voltage at the first drain terminal and generate a second voltage at the second source terminal, and a comparator arranged to receive the second voltage, and transition the first transistor from an on state to an off state in response to the first transistor entering its saturation region of operation. In one aspect, the first transistor includes gallium nitride (GaN). In another aspect, the circuit further includes a logic circuit arranged to receive an output voltage generated by the comparator and to drive the first gate terminal.

Abstract: Circuits and methods that control a rate of change of a drain voltage as a function of time in a transistor are disclosed. In one aspect, the circuit includes a transistor having a gate terminal that controls operation of the transistor, and a control circuit coupled to the gate terminal and arranged to change a voltage at the gate terminal at a first rate of voltage with respect to time from a first voltage to a first intermediate voltage, and further arranged to change the voltage at the gate terminal at a second rate of voltage with respect to time from the first intermediate voltage to a second intermediate voltage, where the first rate is different than the second rate.

Abstract: A GaN half bridge circuit is disclosed. The circuit includes a bootstrap power supply voltage generator is configured to supply a first power voltage and includes a switch node. The circuit also includes a bootstrap transistor, a bootstrap transistor drive circuit, and a bootstrap capacitor connected to the switch node and to the bootstrap transistor. The bootstrap capacitor is configured to supply the first power voltage while the voltage at the switch node is equal to the second switch node voltage, the bootstrap transistor is configured to electrically connect the bootstrap capacitor to a power node at a second power voltage while the voltage at the switch node is equal to the first switch node voltage, and the bootstrap power supply voltage generator does not include a separate diode in parallel with the drain and source of the bootstrap transistor.

Abstract: An electronic power conversion component includes an electrically conductive package base comprising a source terminal, a drain terminal, at least one I/O terminal and a die-attach pad wherein the source terminal is electrically isolated from the die-attach pad. A GaN-based semiconductor die is secured to the die attach pad and includes a power transistor having a source and a drain, wherein the source is electrically coupled to the source terminal and the drain is electrically coupled to the drain terminal. A plurality of wirebonds electrically couple the source to the source terminal and the drain to the drain terminal. An encapsulant is formed over the GaN-based semiconductor die, the plurality of wirebonds and at least a top surface of the package base.

Abstract: Systems and methods that automatically detect state of switches in power converters are disclosed. In one aspect, a power switch includes a first switch coupled between a power input node and a first terminal of a load, a second switch coupled between the power input node and a second terminal of the load, first and second current sense devices arranged to transmit first and second signals including at least one of a magnitude and polarity of first and second currents through the first and second switches, respectively, a first driver circuit arranged to transmit first control signals to the first switch based at least in part on a voltage at the power input node and the first signal, and a second driver circuit arranged to transmit second control signals to the second switch based at least in part on the voltage at the power input node and the second signal.

Abstract: A circuit is disclosed. The circuit includes a first transistor including a first drain terminal, a first gate terminal and a first source terminal, a depletion-mode transistor including a second drain terminal, a second gate terminal and a second source terminal, the second drain terminal connected to the first drain terminal, the depletion-mode transistor arranged to sense a first voltage at the first drain terminal and generate a second voltage at the second source terminal, and a comparator arranged to receive the second voltage, and transition the first transistor from an on state to an off state in response to the first transistor entering its saturation region of operation. In one aspect, the first transistor includes gallium nitride (GaN). In another aspect, the circuit further includes a logic circuit arranged to receive an output voltage generated by the comparator and to drive the first gate terminal.

Abstract: Systems and methods for a GaN-based motor drive circuit using synchronous rectification is disclosed. In one aspect, a method of operating a motor drive circuit includes providing a half-bridge circuit including a high-side GaN switch and a low-side GaN switch coupled in series at an output node, providing a motor coupled to the output node, turning on the high-side GaN switch such that a first current flows through the motor, turning off the high-side GaN switch, turning on the low-side GaN switch when a voltage at the output node drops below a predetermined threshold voltage, sensing, using a sense device coupled to the low-side GaN switch, a magnitude of a second current that flows through the low-side GaN switch, and turning off the low-side GaN switch when the magnitude of the second current drops below a predetermined threshold current.

Abstract: GaN-based half bridge power conversion circuits employ control, support and logic functions that are monolithically integrated on the same devices as the power transistors. In some embodiments a low side GaN device communicates through one or more level shift circuits with a high side GaN device. Various embodiments of level shift circuits and their inventive aspects are disclosed.

Abstract: GaN-based half bridge power conversion circuits employ control, support and logic functions that are monolithically integrated on the same devices as the power transistors. In some embodiments a low side GaN device communicates through one or more level shift circuits with a high side GaN device. Various embodiments of level shift circuits and their inventive aspects are disclosed.