A circuit includes a voltage detection path having a first transistor and a second transistor coupled to the first voltage detection path by a first terminal of the second transistor. The first voltage detection path includes: a first current source and a first voltage divider unit coupled to the first current source. The first transistor is coupled to the first voltage divider unit by a first terminal of the first transistor. A first voltage value at a second terminal of the first transistor is configured to switch between a first high voltage value and a first low voltage value at least partially based on a first detection voltage value provided at the first terminal of the first transistor by the first voltage divider unit. A second voltage at a second terminal of the second transistor is configured to switch between a second high voltage value and a second low voltage value at least partially based on the first voltage value at the second terminal of the first transistor.

Disclosed are a series regulator and electronic equipment. The series regulator includes a first amplifier that drives a first transistor connected between a power supply and a load, a second amplifier that drives a second transistor connected in parallel to the first transistor, an amplifier control circuit that controls whether or not operation of the first amplifier is possible according to the load, and a first overcurrent protection circuit that limits a first output current flowing in the first transistor to a first overcurrent set value or smaller. The first overcurrent protection circuit carries out variable control of the first overcurrent set value according to a second output current flowing in the second transistor. The electronic equipment includes the series regulator and a load that receives power supply from the series regulator and operates.

A voltage regulator includes an operational amplifier that compares a feedback voltage that is proportional to an output voltage and a predetermined reference voltage that corresponds to a desired output voltage. The operational amplifier controls the conduction state of an output transistor according to the comparison. A detecting circuit monitors the operating state of the operational amplifier, and in the case that the operational amplifier is not operating, outputs a signal which causes the output transistor to be placed in a non-conductive state.

A voltage regulator includes an operational amplifier that compares a feedback voltage that is proportional to an output voltage and a predetermined reference voltage that corresponds to a desired output voltage. The operational amplifier controls the conduction state of an output transistor according to the comparison. A detecting circuit monitors the operating state of the operational amplifier, and in the case that the operational amplifier is not operating, outputs a signal which causes the output transistor to be placed in a non-conductive state.

A multiple-output load driving device includes a plurality of output terminals (OUT1 to OUT4) for outputting an output current to each of a plurality of loads (Z1 to Z4), a control portion (8) configured to select either a non-DC current mode in which a non-DC current is used as the output current or a DC current mode in which a DC current is used as the output current, and a first terminal (MSET2). In a case where a low-level signal is supplied to the first terminal, in the non-DC current mode, the non-DC current is outputted from all of the plurality of output terminals. In a case where a high-level signal is supplied to the first terminal, in the non-DC current mode, the DC current is outputted from a predetermined one (OUT4) of the output terminals, while the non-DC current is outputted from the other output terminals (OUT1 to OUT3).

A multiple-output load driving device includes a plurality of output terminals (OUT1 to OUT4) for outputting an output current to each of a plurality of loads (Z1 to Z4), a control portion (8) configured to select either a non-DC current mode in which a non-DC current is used as the output current or a DC current mode in which a DC current is used as the output current, and a first terminal (MSET2). In a case where a low-level signal is supplied to the first terminal, in the non-DC current mode, the non-DC current is outputted from all of the plurality of output terminals. In a case where a high-level signal is supplied to the first terminal, in the non-DC current mode, the DC current is outputted from a predetermined one (OUT4) of the output terminals, while the non-DC current is outputted from the other output terminals (OUT1 to OUT3).

The linear power regulator includes a source follower configured to determine an output voltage of the linear power regulator based on a reference voltage signal applied from outside, a pass-transistor connected to a source end of the source follower and configured to provide a current to a load of the linear power regulator, a negative feedback loop formed by connecting a drain terminal of the source follower and a gate of the pass-transistor, and a negative feedback coefficient controller disposed between the drain terminal of the source follower and the gate of the pass-transistor, and configured to control a negative feedback coefficient of the negative feedback loop by changing the negative feedback coefficient of the negative feedback loop based on an elapsed time from a point in time at which a power signal is applied to the linear power regulator.

The linear power regulator includes a source follower configured to determine an output voltage of the linear power regulator based on a reference voltage signal applied from outside, a pass-transistor connected to a source end of the source follower and configured to provide a current to a load of the linear power regulator, a negative feedback loop formed by connecting a drain terminal of the source follower and a gate of the pass-transistor, and a negative feedback coefficient controller disposed between the drain terminal of the source follower and the gate of the pass-transistor, and configured to control a negative feedback coefficient of the negative feedback loop by changing the negative feedback coefficient of the negative feedback loop based on an elapsed time from a point in time at which a power signal is applied to the linear power regulator.

A semiconductor integrated circuit includes an output transistor, an error amplifier, a replica transistor, a current-limiting circuit, and a potential regulation circuit. The output transistor is electrically connected between a power supply-side first node and an output-side second node. The replica transistor is electrically connected between the first node and a fourth node. The replica transistor constitutes a circuit that is configured to operate to correspond to the output transistor. The current-limiting circuit has an input node, that is electrically connected to a fifth node between the fourth node and a first current source, and an output node that is electrically connected to a gate of the output transistor and a gate of the replica transistor. The potential regulation circuit is electrically connected to the second node and the fourth node.

A semiconductor integrated circuit includes an output transistor, an error amplifier, a replica transistor, a current-limiting circuit, and a potential regulation circuit. The output transistor is electrically connected between a power supply-side first node and an output-side second node. The replica transistor is electrically connected between the first node and a fourth node. The replica transistor constitutes a circuit that is configured to operate to correspond to the output transistor. The current-limiting circuit has an input node, that is electrically connected to a fifth node between the fourth node and a first current source, and an output node that is electrically connected to a gate of the output transistor and a gate of the replica transistor. The potential regulation circuit is electrically connected to the second node and the fourth node.