Abstract: The heat sink bus assembly is adapted to be connected to a printed circuit board having conductor structure leading to conductive foil and printed circuit board mounting structure for physically mounting the printed circuit board components and conduct heat to an enclosure. The printed circuit board is adapted to be mounted in a partially sealed enclosure which is relatively highly thermally conductive. The bus assembly has physically secured thereto high heat generating devices and other devices adjacent to the printed circuit board, is energizable to selectively supply power to a portion of the devices secured thereto, and functions to dissipate heat generated by the high heat generating devices secured thereto by conducting the heat to an enclosure.

Abstract: In a "two-wire" multiplexed lighting system, a square wave voltage alternating between positive and negative polarities is delivered by the two wires to both right and left lamps. Each lamp includes a diode, and the diodes are oppositely pulled with respect to each other so that one of the lamps is energized by one polarity of the square wave while the other lamp is energized by the opposite polarity. The magnitude of each polarity relative to ground is twice the continuous D.C. voltage rating of each lamp so that the average voltage applied to each lamp can be equal to the load's maximum continuous rating to thereby provide full intensity illumination.

Abstract: The land vehicle electrical system comprises a cab controller including a microprocessor system and a chassis controller including a microprocessor system. The microprocessor systems have a multiplexed coupling therebetween and each system includes a microprocessor substantially identical to the microprocessor in the other system with the hardware in each system being substantially identical and with each microprocessor having slightly different software. The microprocessor utilized in the chassis controller has analog inputs for direct connection to sensors. A public data link and a private data link are provided between the microprocessors for additional and backup communication between them. Smart switches are coupled to one or both of the microprocessors and each switch includes means for indicating its status, open circuit or closed circuit, to a microprocessor and the microprocessor includes means for reading the status of the switch and for controlling the status of the switch.

Abstract: Protection for D.C. electrical circuit branches against incipient overloads comprises the use of semiconductor devices known as intelligent switches. An intelligent switch comprises a main controlled conduction path whose conductivity is controlled by an external control input. The semiconductor architecture is configured to possess internal self-protection for the main controlled conduction path against incipient current and/or temperature rises exceeding the device's rating by rendering the main controlled conduction path non-conductive when such incipient conditions are sensed. The invention, recognizing that this internal self-protection attribute can be used also to provide protection for external circuit components connected to the switch in the branch, further comprises the elimination of external protective devices from the branch such that the intelligent switch itself provides the entire overload protection within the branch.