Semiconductor integrated circuit device
Aiming to efficiently preventing an increase in power supply noise caused by a variation in consumption current, a semiconductor integrated circuit device of the present invention includes: first and second power supply interconnections that provide power supply to an internal circuit; a power switch that connects the first power supply interconnection and the second power supply interconnection to each other; power supply noise measurement circuits that measure power supply noise of the internal circuit; and a control circuit that controls a conduction state of the power switch on the basis of a result of a measurement performed by the power supply noise measurement circuits.
1 . A semiconductor integrated circuit device comprising:
first and second power supply interconnections providing power supply to an internal circuit;
a power switch connecting the first power supply interconnection to the second power supply interconnection;
a power supply noise measurement circuit measuring power supply noises of the internal circuit; and
a control circuit controlling a conduction state of the power switch in accordance with a result of a measurement performed by the power supply noise measurement circuit.
2 . The semiconductor integrated circuit device according to claim 1 , further comprising
a determination circuit connected between the power supply noise measurement circuit and the control circuit, wherein
the determination circuit compares magnitude of power supply noise in the internal circuit with a predetermined range determined by a reference voltage, and outputs, to the control circuit, a control signal to increase a resistance value of the power switch when the magnitude of the power supply noise exceeds the predetermined range.
3 . The semiconductor integrated circuit device according to claim 2 , further comprising
a memory storing the reference voltage.
4 . The semiconductor integrated circuit device according to claim 2 , wherein
the power supply noise measurement circuit further measures a power supply voltage of the power supply, and
the determination circuit outputs an end signal when the power supply voltage satisfies criteria determined by a determination voltage.
5 . The semiconductor integrated circuit device according to claim 4 , wherein
the determination circuit outputs the end signal and stops control of the power switch performed by the control circuit.
6 . The semiconductor integrated circuit device according to claim 4 , further comprising
a memory storing the determination voltage.
7 . The semiconductor integrated circuit device according to claim 1 , wherein
the power switch has a plurality of power gate switches, and
the control circuit controls the plurality of power gate switches by a continuous voltage value.
8 . The semiconductor integrated circuit device according to claim 1 , wherein
the power switch has a plurality of power gate switches, and
the control circuit controls the number of power gate switches to be turned on among the plurality of power gate switches.