Semiconductor device, semiconductor system, and control method of semiconductor device

A semiconductor device comprising:

• a circuit to be monitored supplied with a first power supply voltage;
• a voltage monitor supplied with a second power supply voltage different from the first power supply voltage and monitors the first power supply voltage;
• and
• a delay monitor that is supplied with the first power supply voltage and monitors a signal propagation period of time of a critical path in the circuit to be monitored,
• wherein the voltage monitor compares the first power supply voltage with a predetermined reference voltage and outputs a first reset signal when the first power supply voltage is lower than the reference voltage,
• wherein when the signal propagation period of time of the critical path in the circuit to be monitored becomes equal to or longer than a predetermined period of time, the delay monitor outputs a second reset signal, and
• wherein the circuit to be monitored is initialized when ether of the first reset signal or the second reset signal is transferred to the circuit to be monitored.