Kabushiki Kaisha Toshiba

Masayasu Doi

Fujio Nomura

Akira Nakajima

Kenji Iida

Yoshirou Aoki

Hiroshi Iwanaga

A DC-DC converter includes a switching circuit having first and second switching elements to which a direct current voltage is supplied, the first and second switching elements periodically operated so that one of the switching elements is turned on while the other one is turned OFF during a period other than a dead time period, a serial circuit in which a first capacitor, and primary windings of first and second inductance elements are connected in series, and a connection is made between an output point of the switching circuit and a reference potential point (or input voltage point), and output circuits including rectifier elements, each of which rectifies a voltage induced by secondary windings of the first and second inductance elements, the output circuits obtaining a direct current output voltage.

DC-DC Converter

There is no period of time when any of switching elements and switching elements is turned on in a certain switching frequency, any one switching element is turned on in a period of time except for a dead time period for the zero voltage switching, the switching elements and the switching elements are turned on and off while shifting the phases by 180 degrees, and switching elements are turned on during a period of time when the currents in a positive direction and an inverse direction are flowing to the output, respectively, to be operated in a discontinuous current mode.

Electric power unit

A DC-DC converter converts a DC input to a predetermined high-voltage DC output according to a predetermined control signal. An output unit has a pair of high- and low-voltage-side output paths and supplies the predetermined high-voltage DC output to a load. An output variation detecting unit has a resistor voltage dividing circuit including high- and low-voltage-side resistors connected in series between the pair of output paths and detects a variation in predetermined high-voltage DC output that follows a variation in the load. An inner shield shields the exterior of the resistor voltage dividing circuit. The inner shield is electrically connected to a node of the high- and-low voltage-side resistors. An outer shield shields the exterior of the inner shield. The outer shield is electrically connected to the low voltage-side output path of the pair of output paths. A control unit receives a voltage component generated across both ends of the low-voltage-side resistor of the resistor voltage dividing circuit, generates the predetermined control signal in accordance with the voltage component, and supplies the predetermined control signal to the DC-DC converter.

Growing community of inventors

Kawasaki, Japan

Masayasu Doi