Patent ID: 6230710
Filing Date: 2001-05-15
Classification: A61G,A61M,H02J

Abstract:
A switching control circuit for use in an electrical power system for a transportable life support system, the switching control circuit providing uninterrupted electrical power to a load of medical and utility devices by switching between one of a set of converted external power sources, provided by one of a set of power converters, and an internal power voltage outputted by a rechargeable internal power source, the switching control circuit comprising:(a) an input power select circuit in electrical communication with the rechargeable internal power source and with the power converters to receive the internal power voltage and the converted external power voltage, respectively, said input power select circuit monitoring the converted external voltage and then selecting and outputting said external power voltage when said external power voltage is larger than a threshold voltage, selecting and outputting the internal power voltage when said external power voltage is smaller than the threshold voltage, said selection of voltage facilitating seamless switching between the internal power voltage and one of the converted external power voltages;(b) a main bus switch in electrical communication with the input power select circuit to receive the selected voltage, the main bus switch controlling application of the selected voltage to the load of medical and utility devices; and(c) a main bus in electrical communication with the bus switch for transporting the selected voltage to the load of medical and utility devices;(d) wherein the main bus switch comprises a field-effect transistor switch.