Abstract: A battery-embedded device includes a substrate having a wiring, a coil fixed to the substrate, a battery fixed to the substrate, and a first temperature detecting element that is disposed on the substrate and configured to detect a temperature of the battery. An occupancy rate of the wiring in a first region of the substrate which is immediately below the first temperature detecting element is lower than an occupancy rate of the wiring in a second region of the substrate other than the first region.

Abstract: A battery-embedded device includes a substrate having a wiring, a coil fixed to the substrate, a battery fixed to the substrate, and a first temperature detecting element that is disposed on the substrate and configured to detect a temperature of the battery. An occupancy rate of the wiring in a first region of the substrate which is immediately below the first temperature detecting element is lower than an occupancy rate of the wiring in a second region of the substrate other than the first region.

Abstract: A DC-DC converter includes first and second switching devices electrically connected in series between an input terminal and a ground terminal, third and fourth switching devices electrically connected in series between an output terminal and the ground terminal, an inductor, a drive circuit that drives the first switching device to turn on and off, a bootstrap capacitor circuit connected electrically to the drive circuit, and a control circuit. The control circuit is operable to turn on and off the switching devices serially connected with each other after a simultaneous-off duration for which both of the switching devices are continuously turned off. The control circuit is operable to charge the bootstrap capacitor by continuously turning on keeping the second switching device for a charging duration while continuously turning off the first switching device for a sustaining duration determined by the simultaneous-off duration and the charging duration.

Abstract: A DC-DC converter includes a switching device, a drive circuit for turning on and off the switching device, a bootstrap capacitor electrically connected to the drive circuit, and a control circuit electrically connected to the drive circuit. The control circuit is operable to charge the bootstrap capacitor for a charging duration periodically at a charging period longer than an on-off period at which the switching device is turned on and off periodically. This DC-DC converter performs efficient boost and step-down operations.

Abstract: A DC-DC converter includes first and second switching devices electrically connected in series between an input terminal and a ground terminal, third and fourth switching devices electrically connected in series between an output terminal and the ground terminal, an inductor, a drive circuit that drives the first switching device to turn on and off, a bootstrap capacitor circuit connected electrically to the drive circuit, and a control circuit. The control circuit is operable to turn on and off the switching devices serially connected with each other after a simultaneous-off duration for which both of the switching devices are continuously turned off. The control circuit is operable to charge the bootstrap capacitor by continuously turning on keeping the second switching device for a charging duration while continuously turning off the first switching device for a sustaining duration determined by the simultaneous-off duration and the charging duration.

Abstract: A DC-DC converter includes a switching device, a drive circuit for turning on and off the switching device, a bootstrap capacitor electrically connected to the drive circuit, and a control circuit electrically connected to the drive circuit. The control circuit is operable to charge the bootstrap capacitor for a charging duration periodically at a charging period longer than an on-off period at which the switching device is turned on and off periodically. This DC-DC converter performs efficient boost and step-down operations.