PURPOSE: To reduce current consumption of a signal transmission circuit comprising a plurality of circuits each repeating charge/discharge of a load capacity.

CONSTITUTION: Load capacities Co1-Co4 are driven, respectively, through signal lines L1-L4. The signal lines L1-L4 are connected through switches Sc1-Sc4 with a power supply line Vcc and through switches Ss1-Ss4 with a ground line Vss. The signal lines L1-L4 are interconnected through switches S1, 2-S3, 4. Two signal lines of different potential are connected to vary the potential of the signal line through redistribution of charges thus eliminating charge/ discharge through the power supply line Vcc and the ground line Vss. When the load capacities Co1-Co4 are equal, the switches are controlled to shift the phase in the potential variation of each signal line by 1/n thus reducing the quantity of charges required for driving the load capacities by a factor of (n) as compared with a case where (n) load capacities are driven independently.