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ShellAlbert / Summary2019

record the reading books in 2019
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zener #7

Open ShellAlbert opened 5 years ago

ShellAlbert commented 5 years ago

QQ截图20190321161557

ShellAlbert commented 5 years ago

1.根据KCL节点电流定律，I=Iz+IL 2.根据I=(Ui-Uz)/R，推出R=(Ui-Uz)/I 3.将1的公式代入2的公式，则有R=(Ui-Uz)/(Iz+IL) 根据数据手册，TL431推荐的稳定电流为1mA~100mA， 由此可见最小稳定电流为1mA，我们的输入电压是5V，输出电压是2.5V， 负载电流IL由于接的是运放的同相输入端，输入阻抗很大，故假设为1mA吧， 则有R=(5V-2.5V)/(1mA+1mA)=1250欧姆。

ShellAlbert commented 5 years ago

QQ截图20190321170351