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| 一、零点漂移 |
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温漂：由于环境温度的变化而引起工作点漂移。
零漂：当输入电压为零时,输出电压偏离零值的变化。
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| 二、“差放”基本形式 |
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静态时，Ui
= 0 U0＝Uc1-Uc2=0
温度上升 两管电流均增加 Uc1、Uc2均下降
ΔIc1=
ΔIc2;
ΔUc1=
ΔUc2
U0＝(Uc1
- ΔUc1
) – (Uc2
- ΔUc2
) = 0
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结论: |
输入信号之差为零时,输出也为零；输入信号之差不为零时,产生输出；
放大倍数为半边电路的放大倍数； 多用一个三极管，达到抑制温漂。
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| 三、具有射级公共电阻的差放电路 |
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