总电阻:R1*(R2+R3)/(R1+R2+R3)+R2
含R3部分分压:E*(R1*(R2+R3)/(R1+R2+R3))/R1*(R2+R3)/(R1+R2+R3)+R2
R3的分压是:E*(R1*R3)/(R1+R2+R3))/R1*(R2+R3)/(R1+R2+R3)+R2
也就是选择R1R2使得这个分压等于E/K时就可以.
总电阻:R1*(R2+R3)/(R1+R2+R3)+R2
含R3部分分压:E*(R1*(R2+R3)/(R1+R2+R3))/R1*(R2+R3)/(R1+R2+R3)+R2
R3的分压是:E*(R1*R3)/(R1+R2+R3))/R1*(R2+R3)/(R1+R2+R3)+R2
也就是选择R1R2使得这个分压等于E/K时就可以.