A semiconductor chip able to reduce wasteful power loss due to a margin of
power supply voltage considering variation of characteristics. A voltage
setting signal for setting the power supply voltage to be supplied to a
target circuit is generated in a voltage controller in the semiconductor
chip based on a delay time of a delay signal of a replica circuit with
respect to a clock signal. The maximum value of power supply voltage set
by the voltage setting signal is restricted to the maximum value of the
power supply voltage determined based on variations in production of the
semiconductor chip. Accordingly, even when the value of the power supply
voltage set based on the delay signal exceeds the maximum value due to
the margin set considering the variation of characteristics, the voltage
setting of the voltage setting signal output to the external power supply
is restricted to the maximum value, so wasteful power loss can be
suppressed.