Abstract: An inverter circuit includes a pair of switching devices coupled in series across high and low sides of a direct current bus. An output line is coupled between the devices for conducting controlled alternating current power produced by timed switching of the devices. A flyback diode is electrically coupled a in parallel with each switching device and is physically positioned adjacent to the opposite switching device in the pair. Conducting paths between each diode and the associated switching device are preferably physically positioned adjacent to conducting paths between the switching devices and the output line. The placement of the elements cancels or reduces parasitic inductance during switching. Three similar arrangements may be provided in parallel in a three phase inverter. The inverter may be incorporated into a power substrate including a rectifying circuit for converting alternating current power to direct current power to be applied to the bus.

Abstract: A multilayer circuit board or laminated circuit board for use in a motor controller is described. The multilayer circuit board is preferably utilized as a power substrate module. The power substrate module includes a mounting area provided in a recess, window or portion of the circuit board where the circuit board is only a single layer thick. The insulated mounting area is provided in a blind via in the multilayer circuit board. The single circuit board layer at the mounting area provides a heat conductive yet highly electrically insulated mounting area for receiving a heat sink. The heat sink can be mounted on a side opposite the electrical device. The heat sink may be standard heat sink or a copper coil directly soldered to the circuit board. The multilayer circuit board includes an enhanced conductive layer for receiving the surface mount device. The enhanced conductive layer preferably includes an insulative frame which holds copper slugs.

Abstract: A multilayer circuit board system or laminated circuit board system for use in a motor controller includes a motherboard, at least one power substrate circuit board, and a capacitor circuit board. The mother board includes mounting areas for receiving the power substrate board and capacitor circuit board at a 90.degree. angle. The capacitor circuit board, power substrate circuit board, and mother circuit board can be interconnected without the use of external connectors or wires. A fan can be disposed at a front edge of the power substrate circuit boards to provide air flow across their planar surfaces.

Abstract: A multilayer circuit board system or laminated circuit board system for use in a motor controller includes at least two motherboards, at least one power substrate circuit board, and a capacitor circuit board. The circuit boards are mounted in an aperture or trench within each mother board. The power substrate module circuit board includes a mounting area provided in a recess, window or portion of the circuit board where the circuit board is only a single layer thick. The single circuit board layer at the mounting area provides a heat conductive yet highly electrically insulated mounting area for receiving a heat sink. The heat sink can be mounted on a side opposite the electrical device. The capacitor circuit board, power substrate circuit board, and mother circuit boards are interconnected without the use of external connectors or wires. The use of two mother boards increases the rigidity of the circuit board system.

Abstract: A power substrate module having a multilayer circuit board or laminated circuit board for use in a motor controller is described. The power substrate module includes pair of switching devices coupled across a direct current bus for converting direct current power from the bus to controlled alternating current power in response to control signals. The circuit board includes a first conductive layer, a second conductive layer and an insulative layer separating the conductive layers. The first and second conductive layers each include a conductive bus region, one of which is coupled to the first switching device and forms a high side of the direct current bus, and the other of which is coupled to the second switching device and forms the low side of the direct current bus.

Abstract: A multilayer circuit board or laminated circuit board for use in a motor controller is described. The multilayer circuit board is preferably utilized as a power substrate module. The power substrate module includes a mounting area provided in a recess, window or portion of the circuit board where the circuit board is only a single layer thick. The insulated mounting area is provided in a blind via in the multilayer circuit board. The single circuit board layer at the mounting area provides a heat conductive yet highly electrically insulated mounting area for receiving a heat sink. The heat sink can be mounted on a side opposite the electrical device. The heat sink may be standard heat sink or a copper coil directly soldered to the circuit board. The multilayer circuit board includes an enhanced conductive layer for receiving the surface mount device. The enhanced conductive layer preferably includes an insulative frame which holds copper slugs.

Abstract: A multilayer circuit board system or laminated circuit board system for use in a motor controller includes a motherboard, at least one power substrate circuit board, and a capacitor circuit board. The power substrate module includes a mounting area provided in a recess, window or portion of the circuit board where the circuit board is only a single layer thick. The single circuit board layer at the mounting area provides a heat conductive yet highly electrically insulated mounting area for receiving a heat sink. The heat sink can be mounted on a side opposite the electrical device. The capacitor circuit board, power substrate circuit board, and mother circuit board are interconnected without the use of external connectors or wires. A flexible circuit board layer or SCM.TM. interconnect interface allows the circuit boards to be connected solely by printed circuit (PC) wires.

Abstract: A multilayer circuit board or laminated circuit board for use in a motor controller is described. The multilayer circuit board is preferably utilized as a power substrate module. The power substrate module includes a mounting area provided in a recess, window or portion of the circuit board where the circuit board is only a single layer thick. The insulated mounting area is provided in a blind via in the multilayer circuit board. The single circuit board layer at the mounting area provides a heat conductive yet highly electrically insulated mounting area for receiving a heat sink. The heat sink can be mounted on a side opposite the electrical device. The heat sink may be standard heat sink or a copper coil directly soldered to the circuit board. The multilayer circuit board includes an enhanced conductive layer for receiving the surface mount device. The enhanced conductive layer preferably includes an insulative frame which holds copper slugs.

Abstract: A power transistor control circuit for controlling the bias input to the power transducer. During normal operations two switching transistors bias the base input to a power transistor positively and negatively to turn the power transistor on and off. By back biasing a conducting transistor, however, the blocking voltage capability of the transistor is diminished. To maintain blocking voltage at a maximum, the present circuit senses overcurrent conditions indicating a problem condition exists and turns off the power transistor by neutrally biasing a base input. Preferably, both switching transistors used to bias the base input during normal operation of the transistor are rendered nonconductive to accomplish this neutral biasing.