PURPOSE: To eliminate interference between a bipolar logic element and a bipolar driving element formed on the same semiconductor substrate, by forming separately at lest one pad of the power wiring of the logic element and the pad of the power wiring of the driving lement.

CONSTITUTION: On IC chip 51, I2L circuit region 52, ECL circuit region 53, and LED driver circuit region 54 are arranged. Next, main line 55 for the LED driver circuit power wiring is connected to power bonding pad 56, and main line 57 for the ECL driver power wiring is to another power bonding pad 58 formd separatly. As a result, the both are isolated ether other and never interfere multually. Further, main line 59 for the I2L circuit power wiring of region 52 is connected to main line 55 at point B via a constant current circuit not shown in the figure, thereby preventing influence upon the operation of region 52 even if the potential at point B changes by region 54.