Abstract: In order to increase the transient response speed of a DC-to-DC converter capable of voltage step-up and voltage step-down, to which a DC voltage is input from a battery or the like and from which a controlled DC voltage is supplied to a load, a first voltage E1 lower than an output setting voltage Eset by a predetermined voltage is defined and is compared with a DC output voltage Eo by a first comparator, and the result of the comparison is output. @a A second voltage E2 lower than a DC input voltage Ei by a predetermined voltage is defined and is compared with the DC output voltage Eo by a second comparator 133, and the result of the comparison is also output. When the results of the comparisons are represented by Eo<E1 and Eo<E2, a switch connected between the input and the output is turned ON. This configuration greatly increases the response speed at the time when the DC output voltage Eo reaches the output setting voltage Eset.

Abstract: In order to increase the transient response speed of a DC-to-DC converter capable of voltage step-up and voltage step-down, to which a DC voltage is input from a battery or the like and from which a controlled DC voltage is supplied to a load, a first voltage E1 lower than an output setting voltage Eset by a predetermined voltage is defined and is compared with a DC output voltage Eo by a first comparator, and the result of the comparison is output. @a A second voltage E2 lower than a DC input voltage Ei by a predetermined voltage is defined and is compared with the DC output voltage Eo by a second comparator 133, and the result of the comparison is also output. When the results of the comparisons are represented by Eo<E1 and Eo<E2, a switch connected between the input and the output is turned ON. This configuration greatly increases the response speed at the time when the DC output voltage Eo reaches the output setting voltage Eset.

Abstract: A lateral thyristor is provided which includes a semiconductor substrate of a first conductivity type, an epitaxial layer of a second conductivity type formed on the semiconductor substrate, an anode diffusion layer of the first conductivity type formed in the epitaxial layer, a gate diffusion layer of the first conductivity type formed in the epitaxial layer, and a buried layer of the second conductivity type formed below the anode diffusion layer and extending between the semiconductor substrate and the epitaxial layer, wherein there is a region directly below the anode diffusion layer where the anode diffusion layer and the buried layer do not overlap each other, when the lateral thyristor is looked down upon in a direction perpendicular to the principal surface of the semiconductor substrate.