Design of Low-Voltage Bipolar Operational Amplifiers.

摘要

The research presented in the thesis involves the design and implementation of low-voltage bipolar Operational Amplifiers (OpAmps). The OpAmp is an active device that is able to amplify the difference of two input signals with a very high amplification factor to a single output signal. Because of the very high amplification, the use of the OpAmp requires the application of external feedback. In this way, very accurate signal operations can be realized. In Chapter 1 of the thesis, the question is answered why a bipolar low-voltage design is chosen. Further, the objectives of the work are defined and some design considerations are given. In Chapter 2, input stages are discussed. Chapter 3 deals with output stages. In addition to the input and output stage, the OpAmp comprises several other circuit parts. All these circuit parts are briefly discussed in Chapter 4. Both the Miller compensation and the multi-path-driven Miller compensation are thoroughly analyzed in Chapter 5. In Chapter 6, several realizations are evaluated and the measurements that have been performed to verify the theory are discussed. In the final Chapter, the major conclusions of the thesis are recapitulated and some subjects for further research are suggested.