A relationship between distance from a back bias control section which outputs a control signal for controlling a back bias of a transistor and an amount of noise in the control signal outputted from the back bias control section is found. An increase of jitter corresponding to the amount of the noise in a clock transmitted on a clock path connected to a circuit section (IP macro) is found on the basis of the relationship between the distance from the back bias control section and the amount of the noise. The circuit section and the clock path are placed on the basis of the increase of the jitter and an allowable jitter value for the circuit section.