An integrated circuit with a power-on-reset circuit includes an inverter circuit connected between the first and second supply node, a cascode-connected series of transistors MCn, for n going from 1 to N, connected between the first supply node and the input node of the inverter, and a resistive element connected between the input node of the inverter and the second supply node. The transistors in the cascode-connected series of transistors MCn pull up the input node voltage above a trip point voltage when the voltage between the input node and the first supply node is more than a threshold of the cascode-connected series. A circuit connected between the first and second supply nodes is responsive to a POR pulse output by the inverter.

A power on reset circuit according to the present disclosure includes: a reference voltage generating circuit that generates a reference voltage, and also outputs, as a control voltage, a voltage at a node at which a voltage rise is slower than the reference voltage; a comparison voltage generating circuit that operates in response to the control voltage output from the reference voltage generating circuit, and outputs a comparison voltage depending on a power source voltage; and a comparison circuit that compares the comparison voltage output from the comparison voltage generating circuit to the reference voltage output from the reference voltage generating circuit, and outputs an operation signal while the comparison voltage exceeds the reference voltage.

A power on reset circuit according to the present disclosure includes: a reference voltage generating circuit that generates a reference voltage, and also outputs, as a control voltage, a voltage at a node at which a voltage rise is slower than the reference voltage; a comparison voltage generating circuit that operates in response to the control voltage output from the reference voltage generating circuit, and outputs a comparison voltage depending on a power source voltage; and a comparison circuit that compares the comparison voltage output from the comparison voltage generating circuit to the reference voltage output from the reference voltage generating circuit, and outputs an operation signal while the comparison voltage exceeds the reference voltage.

According to a first aspect of the present disclosure, a power switching circuit is provided, comprising: a bandgap reference circuit configured to receive an input voltage and to generate a reference voltage in response to receiving said input voltage; a supply selection circuit configured to receive at least two supply voltages, to select the highest voltage of said supply voltages and to provide said highest voltage to the bandgap reference circuit. According to a second aspect of the present disclosure, a corresponding method of operating a power switching circuit is conceived.

A data processing device according to one or more embodiment is disclosed. The data processing device may include a first power-on reset circuit that generates a first power-on reset signal depending on power source voltage, and a processor that activates based on a first power-on reset signal generated by the first power-on reset circuit and that runs software. The processor determines if the normal first power-on reset signal is used to cause the processor to activate and run the software.

A data processing device according to one or more embodiment is disclosed. The data processing device may include a first power-on reset circuit that generates a first power-on reset signal depending on power source voltage, and a processor that activates based on a first power-on reset signal generated by the first power-on reset circuit and that runs software. The processor determines if the normal first power-on reset signal is used to cause the processor to activate and run the software.

A voltage supply circuit for an electronic circuit includes a switch configured to selectively connect a supply input of the electronic circuit with a main supply voltage source. An auxiliary voltage supply unit has an auxiliary voltage output coupled to the supply input of the electronic circuit. The auxiliary voltage supply unit is configured to at least temporarily output an auxiliary voltage to the supply input. The auxiliary voltage has a voltage level lower than a voltage level of a main supply voltage supplied by the main supply voltage source.

A semiconductor device including an input terminal to which a power source, for which the time until a voltage equal or greater than a predetermined voltage value is output fluctuates according to an external environment, is connected, a power source section to which the input terminal supplies power from the power source, a power source supply terminal that supplies power to a driven semiconductor device, a switch that controls a connection between the power source section and the power source supply terminal, and a voltage regulator to which the input terminal supplies power from the power source, and that supplies a voltage to the power source supply terminal is provided.

A semiconductor device including an input terminal to which a power source, for which the time until a voltage equal or greater than a predetermined voltage value is output fluctuates according to an external environment, is connected, a power source section to which the input terminal supplies power from the power source, a power source supply terminal that supplies power to a driven semiconductor device, a switch that controls a connection between the power source section and the power source supply terminal, and a voltage regulator to which the input terminal supplies power from the power source, and that supplies a voltage to the power source supply terminal is provided.

Voltage surge is prevented when the output from a driver of a driving circuit performs a hard shutdown. In this manner, the elements in the driving circuit are prevented from being damaged by the voltage surge. A driving circuit includes a level shift circuit configured to convert an input signal from a preceding-stage circuit into an output signal having a higher voltage than the input signal, and a controller configured to determine whether a switch element is to perform a soft shutdown based on a state signal indicating a state of the preceding-stage circuit. Here, the driving circuit is configured to drive the switch element.