Abstract: A vapor chamber that includes a housing including a first sheet and a second sheet opposing each other and having respective outer edges of the first sheet and the second sheet joined together; an operation fluid enclosed in the housing; a wick on an inner surface of the first sheet and/or an inner surface of the second sheet; a first pillar on the inner surface of the first sheet and/or the inner surface of the second sheet and that defines a cavity in the housing; and a second pillar on the inner surface of the first sheet and/or the inner surface of the second sheet and configured to prevent the housing from being warped when heated to join the first sheet and the second sheet together.

Abstract: A circuit block assembly is provided that includes circuit blocks that each include a circuit board and a semiconductor element that is disposed on a first main surface of the circuit board. Moreover, each of the circuit blocks includes a metal heat spreader that is connected to the semiconductor element directly or by a thermally conductive member interposed therebetween. A thermally conductive sheet is provided that is thermally connected to the heat spreader. The thermally conductive sheet has a specific electrical resistance higher than a specific electrical resistance of the heat spreader.

Abstract: An electronic device includes an antenna, and a plate-shaped heat spreader including first and second metal layers that are stacked, a working fluid in an enclosed space interposed between the first and second metal layers, and a joint along which outer peripheral portions around the enclosed space are joined. The heat spreader includes an operational region in which the enclosed space is located and a quasi-operational region other than the enclosed space. The antenna is provided in the quasi-operational region in a plan view of the heat spreader.

Abstract: A structure includes a first substrate having at least one of a heat-generating first electronic component and a thermally conductive first component, a second substrate having at least one of a heat-generating second electronic component and a thermally conductive second component, and a vapor chamber between the first substrate and the second substrate such that at least one of the heat-generating first electronic component and the thermally conductive first component is thermally connected to the vapor chamber, and at least one of the heat-generating second electronic component and the thermally conductive second component is thermally connected to the vapor chamber.

Abstract: A circuit block assembly is provided that includes circuit blocks that each include a circuit board and a semiconductor element that is disposed on a first main surface of the circuit board. Moreover, each of the circuit blocks includes a metal heat spreader that is connected to the semiconductor element directly or by a thermally conductive member interposed therebetween. A thermally conductive sheet is provided that is thermally connected to the heat spreader. The thermally conductive sheet has a specific electrical resistance higher than a specific electrical resistance of the heat spreader.

Abstract: An electronic device includes an antenna, and a plate-shaped heat spreader including first and second metal layers that are stacked, a working fluid in an enclosed space interposed between the first and second metal layers, and a joint along which outer peripheral portions around the enclosed space are joined. The heat spreader includes an operational region in which the enclosed space is located and a quasi-operational region other than the enclosed space. The antenna is provided in the quasi-operational region in a plan view of the heat spreader.

Abstract: An AC adaptor is provided that includes a piezoelectric transformer, a switching circuit that is connected to an input electrode of the piezoelectric transformer and performs conversion of an input voltage by turning on and turning off switching elements. Moreover, a diode bridge and a smoothing capacitor are connected to output electrodes and a parallel circuit is connected between an input electrode and the switching circuit and includes a capacitor and a diode. In addition, a rectifying and smoothing circuit is connected in parallel with the parallel circuit and includes a diode and a capacitor. Accordingly, a power supply circuit and an AC adaptor are provided that generate an auxiliary power supply without hindering reduction in size.