問題詳情

3 下圖理想運算放大器電路中，若輸入 vI1 = 4 + 0.125 sinωt (V)、vI2 = -4 (V)時輸出 vO = -0.5 sinωt (V)，則下列敘述何者正確？
(A)R1 = 10 kΩ，R2 = 10 kΩ
(B) R1 = 15 kΩ，R2 = 10 kΩ
(C)R1 = 20 kΩ，R2 = 15 kΩ
(D)R1 = 25 kΩ，R2 = 25 kΩ

參考答案

答案：D
難度：簡單0.723684
統計：A(6),B(1),C(6),D(55),E(0)

用户評論

【lexmvrk】評論

不懂

【V字白喵(107鐵特上榜-】評論

無直流，R1=R2。Vref準位=0.125 sinωt* R2/(R1+R2) =0.125 sinωt* (1/2) = 1/16 sinωtVo/Vref = -100k/(R1//R2)-(1/2)/(1/16) = -8  因為 -100k/(R1//R2) = -8所以 (R1//R2) = -100/-8 = 12.5既然 (R1//R2) = 12.5 R1=R2=25

【V字白喵】評論

無直流，R1=R2。Vref準位=0.125 sinωt* R2/(R1+R2) =0.125 sinωt* (1/2) = 1/16 sinωtVo/Vref = -100k/(R1//R2)-(1/2)/(1/16) = -8  因為 -100k/(R1//R2) = -8所以 (R1//R2) = -100/-8 = 12.5既然 (R1//R2) = 12.5 R1=R2=25