modified 8 years ago

Op-Amp summing circuits.

00:34:34

Blue: If all resistors are equal, the final output voltage is the (negative) sum of all input voltages.

Green: If the feedback resistor value is equal to the total parallel input resistance, the output voltage is the (negative) average of all input voltages.

If the input resistors values are each different, each input voltage will have a different weight on the output average voltage, given by (Rf/Rx)Vi.
So, the bigger the value of an input resistor the less weight that input voltage will have on the output average voltage, and the smaller the value of an input resistor the more weight that input voltage will have in the average output voltage.

published 8 years ago

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.