Abstract: A first transistor has one end and a gate coupled to a first power supply line and other end coupled to a first node. A second transistor has a gate coupled to a second node, one end coupled to the first node, and other end coupled to a third node. A third transistor has one end coupled to a second power supply line, a gate coupled to a fourth node, and other end coupled to the third node. A first bias voltage generation circuit supplies a first bias voltage to the second node. A second bias voltage generation circuit supplies a second bias voltage to the fourth node. Accordingly, the power supply voltage at which the third node is changed from a certain level to another level is set high, and an internal node in a semiconductor device is securely initialized when the power supply voltage is decreased.

Abstract: A first transistor has one end and a gate coupled to a first power supply line and other end coupled to a first node. A second transistor has a gate coupled to a second node, one end coupled to the first node, and other end coupled to a third node. A third transistor has one end coupled to a second power supply line, a gate coupled to a fourth node, and other end coupled to the third node. A first bias voltage generation circuit supplies a first bias voltage to the second node. A second bias voltage generation circuit supplies a second bias voltage to the fourth node. Accordingly, the power supply voltage at which the third node is changed from a certain level to another level is set high, and an internal node in a semiconductor device is securely initialized when the power supply voltage is decreased.

Abstract: A power supply voltage detection circuit is provided including: a first switch to connect between a power supply voltage terminal and a first terminal according to a power supply voltage detection signal and an external signal; a second switch to connect between a reference potential terminal and a second terminal according to the power supply voltage detection signal and the external signal; a first resistance connected between the second terminal and the power supply voltage terminal; and a third switch connecting between the first terminal and the reference potential terminal according to a voltage of the second terminal; and an output circuit outputting the power supply voltage detection signal based on a signal from the first terminal.

Abstract: A power supply voltage detection circuit is provided including: a first switch to connect between a power supply voltage terminal and a first terminal according to a power supply voltage detection signal and an external signal; a second switch to connect between a reference potential terminal and a second terminal according to the power supply voltage detection signal and the external signal; a first resistance connected between the second terminal and the power supply voltage terminal; and a third switch connecting between the first terminal and the reference potential terminal according to a voltage of the second terminal; and an output circuit outputting the power supply voltage detection signal based on a signal from the first terminal.