Abstract: A monolithic microwave semiconductor integrated circuit including a bias stabilizing circuit of a current mirror type formed of a bias control transistor formed of an enhancement mode compound semiconductor field effect transistor and a biased transistor formed of an enhancement mode compound semiconductor field effect transistor.

Abstract: A monolithic microwave semiconductor integrated circuit including a bias stabilizing circuit of a current mirror type formed of a bias control transistor formed of an enhancement mode compound semiconductor field effect transistor and a biased transistor formed of an enhancement mode compound semiconductor field effect transistor.

Abstract: A semi-insulating compound semiconductor device includes an input terminal portion having a protection diode connected thereto and an element formation region and which is provided with a conduction region having the highest potential in the semiconductor device disposed between the input terminal portion and the element formation region. With such an arrangement, low-frequency oscillation of the drain current I.sub.D or drain conductance g.sub.m due to a leak age current from the protection diode connected to the input terminal portion can be prevented from occurring and thus the semi-insulating compound semiconductor device can operate satisfactorily with stabilized characteristics.

Abstract: A two phase voltage signal generating circuit for generating a pair of trapezoidal wave signals of phases opposite to each other is disclosed which includes an input terminal supplied with an input pulse signal, a capacitor, a pair of voltage limiting circuits connected to both ends of the capacitor respectively and for limiting the voltage at each end of the capacitor within a predetermined voltage range, a current control circuit controlled by the input pulse signal and for supplying a charge or discharge current to the capacitor to generate the pair of trapezoidal wave voltage signals at the both ends of the capacitor, a detecting circuit for detecting the change of the intermediate voltage of the trapezoidal wave voltage signals and a symmetry control circuit controlled by an output of the detecting circuit and for controlling the charge or discharge current such that the pair of trapezoidal wave voltage signals become substantially symmetrical to each other.

Abstract: A buffer circuit includes a main buffer circuit section formed of a pair of complementary input side transistors the bases of which are connected together to an input, a dummy circuit section having the same circuit construction as the main buffer circuit section, and a feedback signal section compares the output from the dummy circuit section with a predetermined value to provide a feedback signal which is supplied to the dummy circuit section and the main buffer circuit section so as to make the output of the dummy circuit section equal to that predetermined value.