Error Analysis of Approximate Calculation of Voltage Divider Biased Common-Emitter Amplifier

• 作者: Jingjing Xue Ke Gong Lijuan Zhong Peng Wang Shuangbo Xie Wenxia Huang Xinwu Chen
• 来源期刊: 电路与系统(英文)
• 学科: 数学
• 关键词: Common-Emitter AMPLIFIER Quiescent Point Thevenin EQUIVALENT Circuit Small Signal AMPLIFIER
• 年，卷（期）: dlyxtyw_2017,（10）
• 页码范围: 247-252
• 页数: 6页
• 分类号: O1

摘要

Voltage divider biasing common emitter amplifier is one of the core contents in analog circuit curriculum, and almost all of traditional textbooks apply approximate calculation method to estimate all characteristic parameters. In calculating quiescent point, transistor base current is generally ignored to get the approximate base potential and emitter current, then other operating parameters, and AC small signal parameters can be acquired. The main purpose of this paper is to compare traditional and Thevenin equivalent methods and to get the difference of the two methods. A Formula is given to calculate the error of the traditional method. Example calculating reveals that the traditional method can generate an error about 10%, and even severe for small signal amplifier with higher quiescent point.