Voltage Comparator

[ratzlaff]

Hey,

First off, I don't know much about analog circuits. I am more of a digital guy.

School Project. We have a phototransister array. We have an LED emitter. Using the array we are trying to figure out where the emitter is with respect to the array.

Like I said we are more comfortable with digital circuits, but we need to do this method. For simplicity we decided to use a winner take all approach. The phototransister with the greatest signal will beat out the others.

I at first thought I could use an op amp circuit, but now I am thinking that that will not work. This is going to be harder than I originally thought.

So basically I want an all-in-one IC that tells us what signal is the greatest. (probably does not exist). Any ideas on how to implement this?

Thank you very much for any suggestions/criticisms.

 

[MikeMl]

How many elements in the array? Is it digitally clocked to a single serial analog output, or are all the elements available at the same time on multiple pins?

 

[ratzlaff]

We have not decided on a firm number of elements in the array. As of now we wanted to have all the elements available at the same time on multiple pins.

 

[MikeMl]

We have not decided on a firm number of elements in the array. As of now we wanted to have all the elements available at the same time on multiple pins.

Bad choice. If you clock the elements out serially, you can do it with one sample-and-hold and one comparator. If you do it where all N elements are available in parallel, it requires (N-1)! comparators.

 

[ronv]

A little more input would be helpful in deciding an approach. Is the emmiter always on? How do you picture the array (minimum number). Is a mico involved? Etc.