This is not an XY problem. I have already decided that the best way to handle the actual application is to use a multiplexer and ADC/MCU to measure all the voltages.
However, I am always keen to find a neat new way to hook up opamps or comparators. This is an 'does this configuration exist in a neat way' question? I've not managed to find one yet through the normal search routes.
Inputs - 6 or so positive signals in the 1v to 2v range
Outputs - one amplifier or comparator output per signal, where that corresponding to the largest (or equivalently the smallest) voltage has a unique, perhaps high output, and all the others have a low and similar output, such that they are already logic-usable levels, or can be compared against a simple threshhold to give logic levels.
Ignore input voltage offsets as being insignificant with respect to the input voltages. Hysteresis is optional. Scalable to any (reasonable) number of inputs.
It's relatively easy to output true for all the signals that are above the average of the inputs. Just form the average with an equal resistor network, then use this voltage for the reference input to each comparator.
What I feel should be possible is some sort of diode feedback, like in an absolute value circuit, where the gain of an amplifier reduces the diode drop to insignificance, and the 'winning' amplifier/comparator silences all the others. However, I've not managed to find a simple configuration yet.
What's a simple configuration? One amp per input, with at most two additional shared ones. One diode, or at a stretch two, per amp, with at most 4 resistors per amplifier, and a few extra shared, with as few as possible needing matched values.
I have the outline of a solution which involves an integrator which controls a common reference level. This level ramps down if no inputs exceed it, and ramps up when any input exceeds it. The level will tend to hunt around the largest level, with the comparator output corresponding to the largest flicking on and off. Replacing the comparators with amplifiers and paying attention to stability may result in a steady output that's suitable.