Rohm Co., Ltd.

Nidec Corporation

Yuhei Yamaguchi

Tetsuo Tateishi

Isao Takobe

Takeshi Nagata

Hisashi Fujihara

Shingo Hashiguchi

Keigo Nakamura

Hiroto Oshita

Shun Fukushima

Yosuke Fukumoto

Ryusuke Sato

Genki Tsuruyama

Akihiro Kawano

Yoju Imamura

Kiyotaka Umemoto

Yoshiaki Yamashita

Takayuki Makino

Tatsuro Kawamoto

Yukihiro Watanabe

Quang Danh Ho

Kosuke Sato

A current mode control type switching power supply device includes a first switch having a first terminal connected to a first application terminal to which an input voltage is applied, and a second switch having a first terminal connected to a second terminal of the first switch and a second terminal connected to a second application terminal to which a predetermined voltage lower than the input voltage is applied. A current sensor is configured to sense current flowing in the second switch. A controller configured to control the first switch and the second switch, wherein the controller is configured to control the first switch and the second switch independently of a difference between the input voltage and an output voltage and in addition in accordance with the current sensed by the current sensor.

Current mode control type switching power supply device

A pulse control devicecomprises: a switch output unitwhich generates a pulse output voltage Vo from a direct-current input voltage Vi and supplies the pulse output voltage Vo to a load (such as a relay coilof a mechanical relay); a low-pass filter unitwhich receives a feedback input of the pulse output voltage Vo and generates a feedback voltage Vfb; and an output feedback control unitwhich receives an input of the feedback voltage Vfb and controls the switch output unitso that an average value of the pulse output voltage Vo becomes constant. The low-pass filter unitmay be configured without a coil.

Pulse control device

A switching power supply device includes a first switch, a second switch, a current sensing portion configured to sense current flowing in the second switch, and a controller configured to control the first and second switches in accordance with the current sensed by the current sensing portion. The controller includes an accumulating portion configured to accumulate information of the current sensed by the current sensing portion during a predetermined period of time while the first switch is in the off state, and reflecting portion configured to start the transmission of the current information accumulated by the accumulating portion before the first switch is changed from the off state to the on state so as to reflect the current information accumulated by the accumulating portion on the slope voltage, and controls the first and second switches in accordance with the slope voltage.

A switching power supply device includes a first switch with a first terminal connectable to an application terminal for the input voltage and a second terminal connectable to the first terminal of an inductor; a second switch with a first terminal connectable to the first terminal of the inductor and a second terminal connectable to an application terminal for a voltage lower than the input voltage; a third switch with a first terminal connectable to the first terminal of the inductor and a second terminal connectable to the second terminal of the inductor; a detector; and a controller. The controller produces, after occurrence or a sign of occurrence of an overshoot in the output voltage is detected by the detector until settlement of the overshoot in the output voltage, a control state in which to keep the first and second switches off and the third switch on.

Switching power supply device

A switching regulator control circuit is used in a switching regulator that converts an input voltage into an output voltage by the switching of a switching device, and generates a switching signal for controlling the ON/OFF operation of the switching device. The switching regulator control circuit has a fault detector and a fault protector. The fault detector detects, based on the duty ratio of the switching signal or a variable correlated to it and included in a control signal used to generate the switching signal, a fault state where the duty ratio falls outside the normal modulation range. The fault protector stops the switching of the switching device when the fault detector detects a fault state.

Switching regulator provided with a fault protector

A stator includes a stator core that includes a core back portion having an annular shape and with a central axis as a center and tooth portions extending from the core back portion to an inside in a radial direction and arranged in a circumferential direction, insulators that are attached to the tooth portions from the inside in the radial direction, a coil that is wound around the insulator, and a cover that supports an inner surface of the insulator opposing the inside in the radial direction from the inside in the radial direction.

Stator and motor

A motor includes a rotor configured to rotate about a central axis extending in an up-down direction, a stator located radially outside the rotor, a bracket located above the stator, a circuit board held by the bracket and disposed along a plane perpendicular to an axial direction, and a bus bar held by the bracket and connected to the circuit board at a terminal connection portion. The bracket includes a board support portion supporting the circuit board from below, and a wall portion protruding upward to be higher than the board support portion and surrounding the circuit board. The wall portion has a cutout portion extending downward from an upper end of the wall portion.

Motor

A switching power supply device includes first to fourth switches sequentially connected in series, an inductor, a first capacitor whose first end is connected to a connection node of the first switch and the second switch and whose second end is connected to a connection node of the third switch, the fourth switch, and the inductor, a second capacitor whose first end is connected to a connection node of the second switch and the third switch, and a controller that controls switching on and off of the first to fourth switches. In at least one of a first pair configured with the first switch and the third switch and a second pair configured with the second switch and the fourth switch, the controller shifts a timing of switching from off to on between two switches.

A linear power supply circuit according to the present invention is provided with: an output transistor provided between an input end to which an input voltage is applied and an output end to which an output voltage is applied; and a driver for driving the output transistor on the basis of the difference between a voltage based on the output voltage and a reference voltage. The driver is provided with: a differential amplifier for outputting a voltage according to the difference between the voltage based on the output voltage and the reference voltage; a capacitor one end of which has an output of the differential amplifier applied thereto and the other end of which has the voltage based on the output voltage applied thereto; a converter for converting a voltage based on the output of the differential amplifier into an electrical current and outputting the electrical current; and an electrical current amplifier for amplifying the electrical current of the output of the converter. The supply voltage of the differential amplifier is a first constant voltage or the input voltage.

Linear power supply circuit

Provided is a motor including: a rotor, a stator, a first and second bearing, a support member, a housing including a first flat part and a cylindrical part, and a bearing holder. The cylindrical part includes: a first inner circumferential surface inside which is provided the stator; a second inner circumferential surface, a distance from the second inner circumferential surface to a central axis being greater than a distance from the first inner circumferential surface to the central axis, and the second inner circumferential surface contacting an outer circumferential surface of the bearing holder; and a stepped surface, connecting the first and the second inner circumferential surfaces, and contacting a lower surface of the bearing holder. The housing further includes a riveting part located on the second inner circumferential surface of the cylindrical part and fixing the bearing holder to the second inner circumferential surface of the cylindrical part.

Motor and electrical product

A linear power supply circuit, includes: output transistor between input terminal where input voltage is applied and output terminal where output voltage is applied; a driver driving the output transistor based on difference between voltage based on the output voltage and reference voltage; and phase compensation circuit, wherein the driver includes differential amplifier outputting voltage corresponding to the difference between the voltage based on the output voltage and the reference voltage, a first capacitance having one end where output of the differential amplifier is applied and the other end where ground potential is applied, a converter converting the voltage based on the output of the differential amplifier into current, and a current amplifier amplifying the current output from the converter, and wherein the phase compensation circuit lowers gain of transfer function of the linear power supply circuit and output capacitor connected to the output terminal.

A linear power supply circuit according to the present invention is provided with: an output transistor provided between an input end to which an input voltage is applied and an output end to which an output voltage is applied; a driver for driving the output transistor; and a feedback unit for feeding, back to the driver, information about an output electrical current that is output from the output end. The driver drives the output transistor on the basis of the difference between a voltage based on the output voltage and a reference voltage, as well as the information.

Growing community of inventors

Kyoto, Japan

Yuhei Yamaguchi