GaAs Op-Amplifier With Class AB Output Stage on p-n-p Bipolar and nJFets

The article discusses an operational amplifier (Op-Amplifier) that is designed to be implemented based on GaAs combined techprocesses, which include nJFet FET and p-n-p bipolar transistors. It should be noted that the proposed circuitry, protected as an object of intellectual property, was created considering the limited element basis of techprocesses (the absence of pJFet field-effect and n-p-n bipolar transistors). At the same time, due to the use of advanced circuit designs, the output stage operates in class AB, and the Op-Amplifier has an increased gain (95 dB). In addition, the Op-Amplifier has a high level of linearity of amplitude response in circuits with 100% total negative feedback (maximum output voltage ±7.5 V at a supply voltage of ±10V and load resistances greater than 2 kΩ). Options for building identical GaAs reference current sources in Op-Amplifier based on nJFet are also considered.