| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit power control system which, when power supply noise occurs in a semiconductor integrated circuit, can reduce the impedance of power supply wiring and the power supply voltage, thereby making it possible to suppress a power supply noise amplitude and cut down power consumption. <P>SOLUTION: A variable voltage source 2, semiconductor integrated circuits 3 and 4 to which the power is supplied, and a power supply control circuit 1 which controls the variable voltage source are included. The semiconductor integrated circuits include a parallel resonance circuit comprised of an inductance 31 and an internal element capacitance 43b, a variable resistance 41 provided on power supply wiring of the parallel resonance circuit, and a voltage sensor 42 which compares the voltage supplied from the variable voltage source to the parallel resonance circuit with a reference voltage and outputs a comparison result. The power supply control circuit selects a value of the variable resistance according to the frequency of a signal flowing in the power supply wiring and sets a prescribed voltage value for the variable voltage source according to the output result of the voltage sensor. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
