Abstract: There is disclosed a semiconductor device, which allows the ripple rejection characteristics to be improved and the operating voltage to be reduced. The semiconductor device comprises a power supply circuit arranged between an input terminal and internal circuits so as to make a connection therebetween, said power supply circuit including a transistor Q41 for supplying each of the internal circuits with a drive voltage and another transistor Q44 for allowing a current to pass therethrough in response to a magnitude of a reference voltage supplied to a base thereof and a magnitude of the drive voltage supplied to an emitter thereof. A part of the circuit composed of transistors Q42, Q43 and a resistor R5 controls a current flowing through of the transistor Q41 based on the current that has passed though the transistor Q44, so that the drive voltage could be set to a value higher than the reference voltage approximately by a magnitude of a forward voltage between the base and the emitter of the transistor Q44.

Abstract: A semiconductor device having a current mirror circuit composed of a first transistor element Q11 and a second transistor element Q12 is used as a single transistor TD. A plurality of transistor elements for composing the first transistor element Q11 on the current referring side and a plurality of transistor elements for composing the second transistor element Q12 on the current reference side are dispersedly disposed to provide a uniform distribution density on a semiconductor substrate possibly.

Abstract: There is disclosed a semiconductor device, which allows the ripple rejection characteristics to be improved and the operating voltage to be reduced. The semiconductor device comprises a power supply circuit arranged between an input terminal and internal circuits so as to make a connection therebetween, said power supply circuit including a transistor Q41 for supplying each of the internal circuits with a drive voltage and another transistor Q44 for allowing a current to pass therethrough in response to a magnitude of a reference voltage supplied to a base thereof and a magnitude of the drive voltage supplied to an emitter thereof. A part of the circuit composed of transistors Q42, Q43 and a resistor R5 controls a current flowing through of the transistor Q41 based on the current that has passed though the transistor Q44, so that the drive voltage could be set to a value higher than the reference voltage approximately by a magnitude of a forward voltage between the base and the emitter of the transistor Q44.

Abstract: The present invention provides a series control type regulator which can decrease rapidly an output voltage regardless of heaviness or lightness of a load when a first transistor for controlling an output voltage is set to a state of stop of operation. When a switching circuit sets the first transistor from a state of operation to a state of stop, at the same time an output capacitor is discharged by causing to a discharge circuit connected in parallel to the output capacitor. The discharge circuit starts operating by turning on a third transistor, which turns on by a current flowing to voltage dividing resistors of a detection circuit being used as a base current. The voltage dividing resistors of the detection circuit are also used as resistors for setting a base current of the third transistor.

Abstract: The disclosed serial control type voltage regulator can prevent current from flowing from a backup capacitor (C1) to the side of the voltage regulator, when the control transistor (Q1) stops operating, reducing the power consumption of the backup voltage supply. In the serial control type voltage regulator having a control transistor (Q1) connected in series between an input terminal (1) and where an output terminal (2), an output voltage detector (6) and an error amplifier (4) are used for comparing an output voltage detected by the output voltage detector with a reference voltage (E3) to control the control transistor, there are provided a first switching element (Q3) for cutting off the output voltage detector (4) when the control transistor (Q1) stops operating and a second switching element (Q4) for cutting off the error amplifier (4) also when the control transistor (Q1) stops operating.