Averaging opamp


Joined Dec 20, 2007
An inverting opamp is a mixer and will add the input voltages.
Then a divide-by-3 attenuator will output their average voltage.
It is inverted so another inverter will correct the polarity.
The second inverter can be the divide-by-3.


Joined Apr 27, 2007
Is there something like an averaging opamp circuit? I have three voltages I would like the average of.
If I understand well, you don't need an op-amp for that (except if you want to use a voltage follower next to the network). A resistor network should do the trick. You can connect the resistors from the nodes to be averaged to a common node. The common node will have the average voltage if the resistors are equal. This technique is used in stereo to mono converters used before the bass filter on an amplifier, in amplifiers that use only one subwoofer for both left and right channels.