HIGH-POWER OPERATIONAL AMPLIFIER Russian patent published in 1994 - IPC

FIELD: electrical and radio engineering. SUBSTANCE: high-power operational amplifier is meant for use in systems of control over motors, in audio amplifiers and measurement equipment. It has operational amplifier and output push-pull stage connected in series, base bias unit, thermal protection unit, reference current source and current reflector. Inverting and noninverting inputs of operational amplifier are inputs of high-power operational amplifier. First and second arms of output push-pull stage are built on composite transistors connected in accord with circuit with common collector. Current-limiting resistors are placed into circuits of emitters of composite transistors. Emitter of first p-n-p transistor is coupled to base bias unit and to base of composite transistor of first arm. Base of first two-collector p-n-p transistor is connected to first collector of same transistor and is linked to proper input of current limiting unit. Emitter of second two-collector p-n-p transistor is connected to its other input. Base of second two-collector p-n-p transistor is linked to first collector of same transistor and to base of composite transistor of second arm. Second collector of first and second two-collector p-n-p transistors are tied up together and are connected to current reflector linked to base and one of collectors of third two-collector p-n-p transistor. High-power operational amplifier includes five n-p-n transistors connected to thermal protection unit, resistive power divider, reference current source and to stabilizer diode. EFFECT: expanded operational capabilities and improved characteristics. 1 dwg