PURPOSE: To prevent the time of carrier storage from causing a problem and to obtain a high frequency oscillation signal, by using a transistor of circuit constitution which is not provided with positive feedback.

CONSTITUTION: The differential amplifying circuit consisting of transistors Q10 and Q11 is provided with the 1st current Miller circuit consisting of Q12 and diode D3, and 2nd∼5th current Miller circuits consisting of Q13 and D3, Q14 and D4,D5 and Q15, and D5 and Q16 respectively. Then resistance R1 and capacitor C1 are connected together. In this constitution, triangular wave output VA having peak value i1×R1 centering on the zero voltage point in both the positive and negative directions appear at one terminal of capacitor C1, and rectangular wave output VB having peak value i1×R1 centering on the zero voltage point in the positive and negative directions also appear at one terminal of resistance R1.