40results about How to "Direct current" patented technology

In a DC-DC converter of synchronous rectifying system, a control circuit of DC-DC converter capable of improving the control voltage value of output voltage at light load and enhancing the power conversion efficiency, and its control method are presented. An inverting input terminal of comparator COMP2 of which non-inverting input terminal is connected to a grounding potential is connected to one terminal of choke coil L1 by way of terminal (X). An output terminal (N1) of comparator COMP2 is connected to a delay circuit DL, and an output terminal (N2) of delay circuit DL is connected to AND gate circuit AND1. The delay circuit DL is a circuit for delaying the transition from high level to low level of input terminal (N1). Excessive power supplied more than demanded by the load at light load is returned to choke coil L1. Elevation of output voltage VOUT due to excess power accumulated in output capacitor C1 can be suppressed.

A substrate bias generator which makes device characteristics stable by supplying a predetermined negative voltage to a substrate and minimally reduces current consumption during a self refresh mode. The substrate bias generator comprises a substrate voltage level detector for inputting a substrate voltage and outputting a signal which drives an oscillator in response to the input level, and a controller for inputting a chip active enable signal, a self refresh mode enable signal and an output signal of the substrate voltage level detector and controlling a switching operation of the substrate voltage level detector in response to the input level.

A selection-addressing-type liquid crystal display selectively addresses a signal line of a pixel unit using groups of three selectors of a selector circuit in a time-division manner. A level converter level shifts selector pulses having a voltage swing corresponding to the external-circuit power supply to selector pulses having a voltage swing corresponding to the internal-circuit power supply. In a non-display region in partial display mode, the level converter is deactivated under the control of a control signal to reduce direct current consumption therein.

A system and method for enhanced operation of an electric vehicle having a main battery for powering an electric drive motor by which the vehicle is drivable, including at least one air intake device operable, in forward motion of the vehicle or when the vehicle is stationary, to capture and channel air in flow through the intake device to at least one turbine adjacent to an outlet end of the air intake device to drive the turbine(s) to generate a first electrical energy at a first energy level and / or including one or more photovoltaic solar panels integrated with or adjacent to one or more body components of the electric vehicle and the one or more photovoltaic solar panels is / are adapted to generate a / the first energy at a / the first energy level. A secondary battery pack connected to an electrical energy outlet of the turbine(s) and / or photovoltaic panels receives the electrical energy generated by the turbine(s) and / or photovoltaic panels. A first auxiliary electric motor is drivable by the secondary battery pack for rotating an output shaft of the first auxiliary electric motor. A second auxiliary electric motor having an input shaft connected to the output shaft of the first auxiliary electric motor has an output terminal connectable to the main battery of the vehicle. A transmission couples the output and input shafts and provides a rotational speed step up from the first to the second of the auxiliary electric motors, whereby the second auxiliary electric motor is drivable to generate a second electrical energy, at a second energy level higher than the first energy level, able to be supplied from the output terminal of the second auxiliary electric motor to the main battery and / or the drive motor of the vehicle.

The invention concerns an HF-surgery device for cutting and / or coagulating biological tissue and a method for same, which in operation monitors the patient skin contact of a connected neutral electrode having at least two separate contact surfaces. The HF-surgery device includes at least one parallel resonant circuit arranged in a patient circuit, at least one measurement energy source arranged in a measurement circuit galvanically separated from the patient circuit for producing a measurement voltage / current acting between the contact surfaces of the neutral electrode, and at least one measuring and computing unit which in operation determines by means of the measurement voltage / current a tissue impedance which is representative of the patient skin contact and which acts between the contact surfaces. An HF-current flows in the patient circuit which is closed in the cutting or coagulation operation and the measurement voltage which is independent of the HF-current can be produced in the measurement circuit. To provide an improved HF-surgery device it is provided according to the invention that the frequency of the measurement voltage source is substantially equal to a resonance frequency of the parallel resonant circuit.