SEMICONDUCTOR INTEGRATED CIRCUIT

PURPOSE:To raise the gain of a differential amplifier circuit without increasing the power consumption by turning on all power switch transistors and, after the inversion of the output level of the circuit is confirmed, turning off part of the transistors for the period during which the output logic value is maintained when the output of the circuit is inverted. CONSTITUTION:Plural power switch transistors Q19e and Q20e are provided in a differential amplifier circuit 15A and, when the output of the circuit 15A is inverted, all of the transistors Q19e and Q20e are turned on and, after the inversion of the output level is confirmed, part Q20e of the transistors is turned off during the period during which the output logic value is maintained. Namely, when the output of the circuit 15A is inverted, the maximum bias circuit is made to flow and, after the inverting operation is confirmed, a relatively small bias current which can hold the output logic value is made to flow. Therefore, the gain of the differential amplifier circuit can be raised without increasing the power consumption.