PURPOSE: To omit a power supply for termination by connecting one end of a termination resistor at the reception side of plural ECL circuits to a common line and connecting a capacitor between the common line and a ground potential.

CONSTITUTION: An output of the ECL circuits 10 is connected respectively to a power supply VEE via a resistor 40. Further, an input to the ECL circuits 20 is grounded via the common line 60 and a capacitor 70. In the circuits 10, a terminal voltage V11 at an input terminal 11 is compared with a comparison voltage VREF, and when the voltage V11 is higher, a terminal voltage V12 at an output terminal 12 is brought into a high level V12H and when lower, the voltage V12 is brought into a low level V12L. Since the circuits 20 conduct similar operation, when lots of the circuits 20 exist, the number of circuits of low level state and the number of circuits in high level state are almost equal in terms of probability. Thus, even if the line 60 is connected to the power supply, the current flowing to/out of the power supply is zero and the potential of the line 60 is equal to an intermediate potential of high/level.