Abstract: High reliability, very high slewing rates and fast settling times are realized in an operational amplifier circuit having a single externally controllable gain stage and an input stage that utilizes complementary bipolar transistors and dielectric isolation. The input stage comprises the parallel arrangement of two emitter-follower composite transistors. Each emitter-follower composite transistor consists of the parallel arrangement of two series connected NPN transistors and two series connected PNP transistors. The transistors are connected so that the base current of the PNP transistors supplies base current to the NPN transistors. Dielectric isolation is provided by means of SiO.sub.2.