Non Inverting Summing Amplifier Formula. If the input resistances are equal the output equation of the above circuit is given as v 0 v a v b v c. Therefore here we are getting the negative output.
The voltage inputs va vb and vc are applied to non inverting input of the opamp. We can apply superposition theory to calculate the v then use standard non inverting feedback gain equation to evaluate the output voltage vout. The output voltage of the circuit is governed by the equation.
Design of non inverting summing circuit is approached by first designing the non inverting amplifier to have the required voltage gain.
A non inverting summing amplifier circuit with three inputs are shown above. Effectively the input to non inverting summing amplifier reduces to the average of input signals. The summing of v1 and v2 is not direct. The design of a summing amplifier using a non inverting amplifier is given below.
