(资料图)

差分放大器

电路传递函数为:

V+=(V1-Vref)R2/(R1+R2)+Vref

V-=(Vout-V2)R1/(R1+R2)+V2

V+=V-

(V1-Vref)R2/(R1+R2)+Vref(R1+R2)/(R1+R2)=(Vout-V2)R1/(R1+R2)+V2(R1+R2)/(R1+R2)

(V1-Vref)R2/(R1+R2)+Vref(R1+R2)/(R1+R2)=(Vout*R1-V2*R1+V2*R1+V2*R2)/(R1+R2)

V1*R2-Vref*R2+Vref*R1+Vref*R2=Vout*R1+V2*R2

Vout*R1=V1*R2+Vref*R1-V2*R2

Vout=(V1-V2)R2/R1+Vref