Innovation and Entrepreneurship Based on Differential Amplifier Circuit Teaching

By discussing the practical application of the theory of analog electronic technology in engineering, this paper solves the problem of lack of knowledge of innovation and entrepreneurship in the course of theoretical basis. Firstly, the basic principle of differential amplifier circuit is analyzed. The fully symmetrical circuit structure is used to suppress the common mode signal and amplify the differential mode signal effectively. Secondly, in practical application, the differential signal lines in printed circuit boards are used to effectively suppress electromagnetic interference. Finally, based on this example, this paper innovatively puts forward the integration of simulated electronic technology and innovation entrepreneurship education in basic engineering courses, hoping to give students inspiration about innovation and entrepreneurship in future teaching. Introduction Differential amplifier circuit is one of the key chapters of analog electronic technology. Differential signal which is used theory of differential amplifier circuit more and more widely used in high-speed circuit design. Differential structure design is often used for the most critical signal in the circuit [1]. Differential signal pairs which are very close to each other will also be closely coupled with each other, which will reduce EMI (Electro Magnetic Interference) emission, there are conductive interference and radiative interference. Conductive interference refers to the coupling of signals from one network to another through conductive media. Radiation interference refers to the interference source coupling its signal (interference) to another network through space. In high speed PCB and system design, high-frequency signal lines, integrated circuit pins, various connectors and so on may become radiation interference sources with antenna characteristics, which can transmit electromagnetic waves and affect the normal work of other systems or other subsystems in the system. The Principle of Differential Amplifier Circuit It is composed of two common emitter amplifier circuits. The output signal is taken from the collector of two tubes. In circuit design, characteristics of the two tubes VT1 and VT2 are identical in fabrication technology, and the resistance and temperature characteristics of the two circuits are identical, that is, the two sides of the circuit are completely symmetrical [2]. In static state, 1 2 0 I I U U     , the static potential of the two collectors, 1 2 C C U U  , and the output voltage are obtained, 0 O U   . When the temperature changes, the collector potential of the two tubes drifts simultaneously. For example, when the temperature rises, 1 C U and 2 C U decreases 1 C U  , 2 C U  at the same time. Because the two sides of the circuit are completely symmetrical, there must be an output voltage, 1 2 C C U U    ,     1 1 2 2 0 O C C C C U U U U U       . There is no 5th International Conference on Education Reform and Modern Management (ERMM 2019) Copyright © 2019, the Authors. Published by Atlantis Press. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/). Advances in Social Science, Education and Humanities Research, volume 361