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1.
图解分析法： 利用晶体管的特性曲线，用作图的方法来分析。
2.
计算分析法： 将具有非线性特性的晶体管近似用线性等效电路来代替，然后利用电路理论求解。
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| 一、用图解法分析静态工作情况 |
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放大电路处于静态时，常用直流量IB、UBE、IC和UCE来描述晶体管的静态工作情况。对应在晶体管的输入特性和输出特性曲线上各确定一点，该点称为静态工作点。 |
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步骤： |
1.
画出直流通路；
2. 利用输入特性曲线来确定IBQ和UBEQ；
3. 利用输出特性曲线确定UCEQ及ICQ。
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（一）画出直流通路 |
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静态时，输入信号电压ui=0，即将信号源短路，就得到放大电路的直流通路。 |
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（二）利用输入特性曲线来确定IBQ和UBEQ |
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1. 晶体管的输入特性曲线
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2.
电路中的输入回路 |
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列方程 |
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该线称直流负载线，它与输入特性的交点Q（
UBEQ，
IBQ）就是静态工作点。 |
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