Patent application number | Description | Published |
20080247108 | Load drive device - A load drive device is provided for outputting a control signal to a driving transistor and for driving a load by switching, the driving transistor and the load being connected in series between a direct current power source and ground. The load drive device includes a reverse connection protection unit which is provided in a line leading from a negative side of the direct current power source, and which blocks a current flowing therethrough when the direct current power source is connected in reverse. A failure detection is performed by a failure detection process by monitoring a change of a current flowing via the reverse connection protection unit during the driving transistor is in a conduction state. | 10-09-2008 |
20080297079 | Rotor position sensing system of brushless motor - A rotor position detecting circuit includes a first position detecting circuit having a low-pass filter that shapes up phase voltage induced in a phase coil and a first comparator that compares the output voltage of the low-pass filter with a threshold level to form a first rotor position signal, and a second position detecting circuit having a second comparator that compares the phase voltage with a threshold voltage and a control unit that digitally processes the output voltage of the second comparator to form a second rotor position signal. The control unit corrects the first rotor position signal by the second rotor position signal to provide a final rotor position signal when the rotation speed of the brushless DC motor is in a measurable range. | 12-04-2008 |
20090109588 | Load driver with wire break detection circuit - A load driver includes a transistor coupled in series with a load, a control circuit for controlling the transistor, and a wire break detection circuit. The wire break detection circuit includes a current detection device and a wire break detection device. The current detection device is coupled between a first point in a wire connecting the control circuit to a ground terminal and a second point in a path through which a load current flows. The wire break detection device determines that a break occurs in the wire, when the current detection device detects an electric current flowing from the first point to the second point. | 04-30-2009 |
20100026355 | Load drive device and control system of the same - A load drive device for driving an inductive load by PWM controlling a switching element includes synchronization control unit, a synchronization signal input terminal, and a synchronization signal output terminal. The synchronization control unit outputs the PWM signal to the switching element. The synchronization control unit receives a synchronization signal through the input terminal from an exterior. The synchronization control unit outputs the synchronization signal through the output terminal to an exterior. When the synchronization control unit does not receive the synchronization signal, the synchronization control unit outputs the synchronization signal such that a first switching period of the PWM signal is prevented from overlapping with a second switching period of a PWM signal of an external device. When the synchronization control unit receives the synchronization signal, the synchronization control unit generates the PWM signal based on the synchronization signal. | 02-04-2010 |
20110268593 | ELECTRIC DEVICE MOUNTED IN ELECTRIC COMPRESSOR - An electric device includes: a circuit board arranged in cooling medium in a housing and having an electric element and an external coupling electrode, wherein the electric element is sealed in and mounted in a substrate, and the electric element is electrically coupled with the external coupling electrode; an external coupling terminal electrically coupled with the external coupling electrode; and a separation member for separating the external coupling terminal and a connection portion between the external coupling electrode and the external coupling terminal away from the cooling medium. | 11-03-2011 |