Abstract: Provided is an electronic device 1, including: a piezoelectric element 30; a panel 10 configured to support the piezoelectric element 30; and a housing 60 configured to hold the panel 10 and conduct a vibration through the panel 10, the panel 10 generating air-conduction sound and vibration sound that is transmitted by vibrating a part of a human body. The housing 60 includes a first housing portion 62 and a second housing portion 61 located inward of the first housing portion 62, and rigidity-reinforcing portions (63, 150; 64, 160; 65, 66, 170) are disposed between the first housing portion 62 and the second housing portion 61 for improving rigidity of the housing 60.

Abstract: A drive device according to one aspect of the disclosure includes a control terminal connector, a switch circuit, a current limit circuit, and a clamp switch on a circuit board. The clamp switch is located in a second quadrant or a fourth quadrant of four quadrants, where the four quadrants are partitioned by two mutually orthogonal virtual lines with the current limit circuit set as an origin and the four quadrants consist of a first quadrant including an area where the control terminal connector is located, the second quadrant, a third quadrant, and the fourth quadrant, in clockwise order.

Abstract: An electronic apparatus that may reduce sound leakage from a housing and the like vibrated by a vibrator and echo caused by the sound leakage is provided. An electronic apparatus includes a panel, a panel retainer for supporting the panel, and an element for vibrating the panel and thereby generating a vibration sound to be delivered via a human body, wherein a region of the panel near a disposing position of the element is thinner in a normal direction of the panel than a remaining region of the panel.

Abstract: A driving apparatus of the present disclosure includes a coil including a second terminal connected to a control terminal of a switching element, a charging switch connected between a first potential line and a first terminal of the coil, a clamp switch connected between the first potential line and the control terminal of the switching element, a charging diode connected between a second potential line and the first terminal of the coil, and a control circuit that outputs a charging control signal for turning on the charging switch and for turning off the charging switch before a potential of the control terminal of the switching element reaches the first potential and a clamp control signal for turning on the clamp switch after the charging switch is turned on.

Abstract: A driving apparatus includes a first potential line that applies a first potential, a second potential line that applies a second potential, a coil including a first terminal and a second second terminal that is connected to a control terminal of a switching element, a charging switch connected between the first potential line and the first terminal of the coil, a clamp switch provided between the first potential line and the second terminal of the coil, a reverse-flow blocking diode connected in series with the clamp switch between the first potential line and the second terminal of the coil, and a control circuit that controls the charging switch and the clamp switch.

Abstract: Provided is an electronic device that generates, by vibrating a vibration body, vibration sound by the vibration. The electronic device executes a side tone function by using sound collected by a microphone 7 during the vibration of the vibration body. When an open/close detector 100 detects a closed state, the electronic device also stops the side tone, improving usability of the electronic device.

Abstract: An echo caused by sound leakage from a housing that vibrates due to a vibrating body is reduced. An electronic device (1) according to the present invention includes a piezoelectric element (30), a vibrating plate (10) that vibrates due to the piezoelectric element (30), microphones (42, 43), and an equalizer (44), the electronic device (1) causing the vibrating plate (10) to generate air-conducted sound and vibration sound that is transmitted by vibrating a part of a human body. The equalizer (44) makes a low-range emphasis setting, to emphasize a low frequency range more than a high frequency range of the air-conducted sound, when the volume of the air-conducted sound collected by the microphones (42, 43) exceeds a predetermined threshold.

Abstract: Provided is an electronic device 1, including: a piezoelectric element 30; a panel 10 configured to support the piezoelectric element 30; and a housing 60 configured to hold the panel 10 and conduct a vibration through the panel 10, the panel 10 generating air-conduction sound and vibration sound that is transmitted by vibrating a part of a human body. The housing 60 includes a first housing portion 62 and a second housing portion 61 located inward of the first housing portion 62, and rigidity-reinforcing portions (63, 150; 64, 160; 65, 66, 170) are disposed between the first housing portion 62 and the second housing portion 61 for improving rigidity of the housing 60.

Abstract: The content of sound leakage from a vibrating plate that vibrates due to a piezoelectric element is made difficult to recognize. An electronic device (1) according to the present invention includes a piezoelectric element (30) and a vibrating plate (10) that vibrates due to the piezoelectric element (30), the electronic device (1) causing the vibrating plate (10) to generate air-conducted sound and vibration sound that is transmitted by vibrating a part of a human body. The electronic device (1) also includes an air-conducted sound reducing unit that makes a portion or all of the air-conducted sound difficult to hear.

Abstract: Provided is an electronic device including: a piezoelectric element; a vibration plate to which the piezoelectric element is joined for vibration; and a housing to which the vibration plate is joined. Vibration sound, which is transmitted by vibrating a part of a human body, is generated by the vibration plate. The vibration plate includes, in a plan view thereof, a first area including a joining portion with the piezoelectric element and a second area located further away from the joining portion than the first area is, and rigidity in a first area is lower than rigidity in the second area. With the above configuration, sound leakage or the like is reduced, and usability of the electronic device is improved.

Abstract: Provided is an electronic device that can be appropriately used as a type of electronic device that vibrates a panel attached to a housing. The electronic device includes a piezoelectric element, a panel, to which the piezoelectric element is attached, that vibrates due to the piezoelectric element to generate a vibration sound transmitted by vibrating a part of a human body, a housing supporting the panel with a first face, a microphone contained within the housing and disposed on a second face, and a buffer that damps vibration transmitted from the panel to the microphone through the first face and/or the second face, thereby reducing noise picked up by the microphone.

Abstract: A semiconductor element including an MISFET exhibits diode characteristics in a reverse direction through an epitaxial channel layer. The semiconductor element includes: a silicon carbide semiconductor substrate of a first conductivity type, semiconductor layer of the first conductivity type, body region of a second conductivity type, source region of the first conductivity type, epitaxial channel layer in contact with the body region, source electrode, gate insulating film, gate electrode and drain electrode. If the voltage applied to the gate electrode is smaller than a threshold voltage, the semiconductor element functions as a diode wherein current flows from the source electrode to the drain electrode through the epitaxial channel layer. The absolute value of the turn-on voltage of this diode is smaller than the turn-on voltage of a body diode that is formed of the body region and the first silicon carbide semiconductor layer.

Abstract: Provided is an electronic device including a housing and an acoustic device configured to generate vibration sound that is transmitted through vibration of a part of a human body. The acoustic device includes a panel configured to be joined to the housing; a piezoelectric element configured to be joined to the panel for vibrating the panel; and a vibration adjusting unit configured to be joined to the panel and vibrated together with the panel by the piezoelectric element. With the above configuration, a frequency characteristic is improved.

Abstract: Provided is an electronic device that is capable of reducing sound leakage from a vibration plate vibrated by a piezoelectric element. An electronic device 1 of the present invention includes: a piezoelectric element 30; and a vibration plate 10 configured to be vibrated by the piezoelectric element 30. Vibration sound is transmitted by the vibration plate vibrating a part of a human body. The piezoelectric element 30 is vibrated using a processed sound signal in which at least a part of frequency components of a sound reproduction signal that are higher than a predetermined threshold value is cut or attenuated.

Abstract: A power converter for effectively reducing switching noise is provided. The power converter comprises a capacitor 111; switching devices Q11a and Q11b connected to the capacitor 111 in parallel; and a controller 105 that controls each switching device individually to perform switching operations. Each of the switching devices Q11a and Q11b forms a closed circuit together with the capacitor 111. The controller 105 controls the switching devices Q11a and Q11b to perform switching operations of switching ON or OFF at different timings such that at least two closed circuits including the switching devices Q11a and Q11b mutually cancel ringing voltages occurring therein, each ringing voltage occurring due to the switching operations performed by a corresponding switching device and having a frequency defined by an inductance of a corresponding closed circuit and an output capacity of a switching device included in the corresponding closed circuit.

Abstract: A power conversion apparatus includes a MOSFET having a channel and a body diode connected in parallel. The channel of the MOSFET becomes conductive according to a control signal, so that a flow path of a regenerative current of an inductor is formed, and the body diode of the MOSFET causes the regenerative current of the inductor to flow in a forward direction. The power conversion apparatus also includes a shunt resistor and a voltage measuring unit which measure an amount of a current flowing into the MOSFET. In addition, the power conversion apparatus includes a threshold designating unit which designates a threshold current amount, and a synchronous rectification prohibiting circuit which prohibits supplying the control signal when the amount of the current measured by the shunt resistor and the voltage measuring unit is greater than the threshold current amount designated by the threshold designating unit.

Abstract: A semiconductor element including an MISFET exhibits diode characteristics in a reverse direction through an epitaxial channel layer. The semiconductor element includes: a silicon carbide semiconductor substrate of a first conductivity type, semiconductor layer of the first conductivity type, body region of a second conductivity type, source region of the first conductivity type, epitaxial channel layer in contact with the body region, source electrode, gate insulating film, gate electrode and drain electrode. If the voltage applied to the gate electrode is smaller than a threshold voltage, the semiconductor element functions as a diode wherein current flows from the source electrode to the drain electrode through the epitaxial channel layer. The absolute value of the turn-on voltage of this diode is smaller than the turn-on voltage of a body diode that is formed of the body region and the first silicon carbide semiconductor layer.

Abstract: An inverter comprising: a circuit including arms connected in parallel, each of the arms including a first switch and a second switch connected in series; and a gate drive circuit configured to control, by pulse-width modulation using synchronous rectification, each of the first switch and the second switch to switch to an on-state or an off-state, wherein each of the first switch and the second switch includes: a channel region that is conductive in both a forward direction and a reverse direction in the on-state, and that is not conductive in the forward direction in the off-state; and a diode region that is combined as one with the channel region, and that is conductive only in the reverse direction, the diode region being unipolar, and the gate drive circuit synchronizes a timing at which the gate drive circuit outputs a signal for causing the first switch to switch to the on-state with a timing at which the gate drive circuit outputs a signal for causing the second switch to switch to the off-state, and

Abstract: A small-sized load drive system which, even with three three-phase inverters, significantly reduces noise regardless of control duty ratio. The load drive system includes three-phase inverters, and first, second, and third control units. The inverters are connected to loads, respectively. The first control unit generates sawtooth wave voltage and controls the inverter according to the sawtooth wave voltage. The second control unit generates inverse sawtooth wave voltage and controls the inverter according to the inverse sawtooth wave voltage. The third control unit generates triangular wave voltage which has ramps respectively equal to the sawtooth/inverse sawtooth wave voltage and either has a same phase or is out of phase by half a period relative to the sawtooth/inverse sawtooth wave voltage, and also controls the inverter according to the triangular wave voltage.

Abstract: An electronic device (1) is provided with a piezoelectric element (30), a panel (10) holding the piezoelectric element (30), and a housing (60) holding the panel (10) and transmitting vibration through the panel (10). The electronic device (1) causes the panel (10) to generate vibration sound that is transmitted by vibrating a part of a human body. The electronic device (1) includes a stiffness varying portion (62, 63) in which the stiffness of the housing (60) varies.