Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: The disclosed invention is intended to prevent malfunction of an internal circuit because of unwanted power supply switching caused by a noise during operation of a semiconductor device powered by a backup power supply, while eliminating wasteful consumption of the backup power supply. A first switching transition time after coupling the main power supply terminal to the internal power supply node until decoupling the backup power supply terminal from the internal power supply node is made longer than a second switching transition time after coupling the backup power supply terminal to the internal power supply node until decoupling the main power supply terminal from the internal power supply node.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: The disclosed invention is intended to prevent malfunction of an internal circuit because of unwanted power supply switching caused by a noise during operation of a semiconductor device powered by a backup power supply, while eliminating wasteful consumption of the backup power supply. A first switching transition time after coupling the main power supply terminal to the internal power supply node until decoupling the backup power supply terminal from the internal power supply node is made longer than a second switching transition time after coupling the backup power supply terminal to the internal power supply node until decoupling the main power supply terminal from the internal power supply node.

Abstract: The disclosed invention is intended to prevent malfunction of an internal circuit because of unwanted power supply switching caused by a noise during operation of a semiconductor device powered by a backup power supply, while eliminating wasteful consumption of the backup power supply. A first switching transition time after coupling the main power supply terminal to the internal power supply node until decoupling the backup power supply terminal from the internal power supply node is made longer than a second switching transition time after coupling the backup power supply terminal to the internal power supply node until decoupling the main power supply terminal from the internal power supply node.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: The disclosed invention is intended to prevent malfunction of an internal circuit because of unwanted power supply switching caused by a noise during operation of a semiconductor device powered by a backup power supply, while eliminating wasteful consumption of the backup power supply. A first switching transition time after coupling the main power supply terminal to the internal power supply node until decoupling the backup power supply terminal from the internal power supply node is made longer than a second switching transition time after coupling the backup power supply terminal to the internal power supply node until decoupling the main power supply terminal from the internal power supply node.

Abstract: To provide a semiconductor device provided with a power-on reset circuit that can reliably detect decrease in power-supply voltage. The power-on reset circuit provided on the semiconductor device includes: a first comparison circuit that compares a primary voltage with a reference value; and a second comparison circuit that compares a secondary voltage with the reference value. The power-on reset circuit issues a reset signal based on comparison results of the first and second comparison circuits.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: A semiconductor device which makes it possible to reduce a wasteful standby time at power-on is provided. In this semiconductor device, a reset of an internal circuit is canceled as described below. When a data signal stored in a storage section is at “0,” the reset is canceled by bringing an internal reset signal to the “H” level when a relatively short time has passed after the rising edge of a power on reset signal. When the data signal is at “1,” the reset is canceled by bringing the internal reset signal to the “H” level when a relatively long time has passed after the rising edge of the power on reset signal. Therefore, a wasteful standby time at power-on can be reduced by writing the data signal logically equivalent to the rise time of supply voltage to the storage section.

Abstract: The present invention is directed to prevent occurrence of a problem on a withstand voltage in a circuit group which receives supply of an internal power supply voltage. An error amplifier outputs a control voltage obtained by amplifying a difference voltage between a reference voltage and a divided voltage obtained by dividing an internal power supply voltage to an output node. A drive transistor supplies a drive current according to the control voltage of the output node of the error amplifier from an external power supply line to an internal power supply line. When the divided voltage exceeds a predetermined voltage, a clamp circuit changes the control voltage in the direction of decreasing the drive current.

Abstract: There is a need to provide a technology that shortens a time period from a point to start an external power supply for a microcontroller to a point to start operating a logic circuit. A stable voltage supply circuit of a semiconductor circuit accepts an external power supply VCC and supplies a VDD line with one of a power supply voltage to cause a stable output voltage and a power supply voltage to cause an unstable output voltage and fast start. At startup, the semiconductor circuit accepts an external power supply. The semiconductor circuit raises a power supply voltage to cause a stable output voltage and supplies a logic portion initialization circuit with an unstable power supply voltage to fast start, and initializes a VDD operation circuit. When the output voltage is stabilized, the semiconductor circuit changes a power supply voltage supplied to the VDD line and starts operating the VDD operation circuit.

Abstract: To provide a semiconductor device provided with a power-on reset circuit that can reliably detect decrease in power-supply voltage. The power-on reset circuit provided on the semiconductor device includes: a first comparison circuit that compares a primary voltage with a reference value; and a second comparison circuit that compares a secondary voltage with the reference value. The power-on reset circuit issues a reset signal based on comparison results of the first and second comparison circuits.

Abstract: The present invention is directed to prevent occurrence of a problem on a withstand voltage in a circuit group which receives supply of an internal power supply voltage. An error amplifier outputs a control voltage obtained by amplifying a difference voltage between a reference voltage and a divided voltage obtained by dividing an internal power supply voltage to an output node. A drive transistor supplies a drive current according to the control voltage of the output node of the error amplifier from an external power supply line to an internal power supply line. When the divided voltage exceeds a predetermined voltage, a clamp circuit changes the control voltage in the direction of decreasing the drive current.

Abstract: To provide a semiconductor device provided with a power-on reset circuit that can reliably detect decrease in power-supply voltage. The power-on reset circuit provided on the semiconductor device includes: a first comparison circuit that compares a primary voltage with a reference value; and a second comparison circuit that compares a secondary voltage with the reference value. The power-on reset circuit issues a reset signal based on comparison results of the first and second comparison circuits.

Abstract: To provide a semiconductor device provided with a power-on reset circuit that can reliably detect decrease in power-supply voltage. The power-on reset circuit provided on the semiconductor device includes: a first comparison circuit that compares a primary voltage with a reference value; and a second comparison circuit that compares a secondary voltage with the reference value. The power-on reset circuit issues a reset signal based on comparison results of the first and second comparison circuits.

Abstract: The present invention is directed to prevent occurrence of a problem on a withstand voltage in a circuit group which receives supply of an internal power supply voltage. An error amplifier outputs a control voltage obtained by amplifying a difference voltage between a reference voltage and a divided voltage obtained by dividing an internal power supply voltage to an output node. A drive transistor supplies a drive current according to the control voltage of the output node of the error amplifier from an external power supply line to an internal power supply line. When the divided voltage exceeds a predetermined voltage, a clamp circuit changes the control voltage in the direction of decreasing the drive current.