FoxCalculators - Free Calculators Online!

Input Parameters (Inverting Op-amp)
Vout	(V)
Gain
R1	(KOhms)
V1 (Input lead)	(V)
V2 (non-zero only if offset is requred)	(V)
Vp	(V)
Vn	(V)
Outputs
R2	(KOhms)
R3	(KOhms)
R4	(KOhms)

<script language="JavaScript"> function Validate(form) { if(!form.Zo.value) { alert("Enter Value for Zo."); form.Zo.focus(); return false; } return true; } function Compute(form) { with(Math) { var Vout = Number(form.Vout.value); var A = Number(form.A.value); var R1 = Number(form.R1.value); var V1= Number(form.V1.value); var V2= Number(form.V2.value); var Vp = Number(form.Vp.value); var Vn = Number(form.Vn.value); var R2; var R3; var R4; var Vout1; // contribution due to V1 var Vout2; // contribution due to V2 var Precision= 3; if(A>0) A= -A; if(Vn==Vp) Vn= -Vp; if(Vn>Vp) { temp=Vp; Vp= Vn; Vn= temp; } if(Vn>0.0) Vn= 0; R2= -A*R1; R3= R1; Vout1= A*V1; Vout2= Vout-Vout1; //R4= Vout2*(R1/(V2*(R1+R2)))*R3 / (1-Vout2*(R1/(V2*(R1+R2)))); R4= R3*(1-Vout2*R1/((R1+R2)*V2))/ (Vout2*R1/((R1+R2)*V2)); form.R2.value= R2.toPrecision(Precision); form.R3.value= R3.toPrecision(Precision); form.R4.value= R4.toPrecision(Precision); form.Vp.value= Vp.toPrecision(Precision); form.Vn.value= Vn.toPrecision(Precision); form.A.value= A.toPrecision(Precision); } } </script>