PURPOSE: To decrease the leading/trailing time and to reduce the phase deviation by adding a capacitor so as to cancel the effect on the leading/trailing of the base-collector capacitance of transistors(TRs) in differential pair.

CONSTITUTION: TRs Q2, Q3 are added to a conventional differential amplifier comprising TRs Q1, Q4, Q5 and resistors RL1, RL2. Thus, the electric charge discharged from the base-collector capacitance of the TR Q1 charges directly the base-collector capacitance of the TR Q3, and the electric charge discharged from the base-collector capacitance of the TR Q2 charges directly the base- collector capacitance of the TR Q4, then the effect of the base-collector capacitance or the TRs Q1, Q4 onto the leading/trailing is cancelled. Thus, the leading/ trailing operation of the TRs Q1, Q4 is quickened and the production of phase deviation based on the level fluctuation of the input signal is suppressed.