how to compare multiple voltages?

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Hi, all

I get several (4-16) DC output voltages, all ranging from 0-3.3v.

and I want to compared all these DC, and choose the highest one as the input signal of my next stage.

what kind of devices should I choose? I searched for "multiple voltage comparator" but found nothing.

Thanks
 

Use as example PIC18F45K22 (can work on 1,8V) which have 28 10-bit ADC channels, take values from channels, compare them and some output pin should switch some MOSFET DC channel on, and other channels turn off.
 

A peak detector could do what you want.

The capacitor automatically charges to whichever is the highest incoming volt level.

This method subtracts a diode drop from all incoming signals. Therefore you should add 0.7 to all of them beforehand, because signals below 0.7 V will get disregarded otherwise.

The transistor can be used to discharge the capacitor. Or install a medium resistance across it, to discharge it gradually.

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