is there a way in which i can calculate resistor values instead of solving this complex equations

Thread Starter

ashokraj

Joined Feb 1, 2018
89
I am desiging non inverting amplifier with inverting postive reference voltage circuit.
I will have to solve these equations to know the resistor values. is there a way i can solve these equations simply by inserting input voltage range, output voltage range, reference voltage?

1591196820729.png
 

DickCappels

Joined Aug 21, 2008
6,461
1591267120203.png



You can make this a lot simpler my looking at the circuit as two circuits and solve each one.

Simply find the values of R3 and R4 to give the offset voltage in the correct proportion to the input voltage. This is a simple resistive voltage divider problem.

After that use the formula below to calculate the resistor values needed to scale the offset signal at the noninverting input to the desired amplitude on the output.

The formula: The output of the amplifier is the voltage on the noninverting input times (1 + (R1/R2)).



/////////////////////////
Gain of a noninvertng amplifier:
1591268189916.png
 
Top