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Priority encoder
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gaminn:
Hi,
I'm looking for a device similar to priority encoder. I have 3 inputs a 3 outputs.

If input 3 is high (no matter what level is on input 2 and 1) then output 3 is high and all other outputs are low
If input 2 is high (no matter what level is on input 1) then output 2 is high and all other outputs are low
If input 1 is high then output 1 is high and all other outputs are low

Is there any IC available that do this logic?
JuanGg:
It should not be too hard to make a truth table and design a circuit with some nand gates to perform the task.
Attached is a schematic that will do with a couple quad nand gates. Something like that, I'm sure there are plenty of ways of doing it.
    Juan

EDIT: Thanks to Renate for pointing out a major simplification.
gaminn:
I know but I hope there is a suitable part that can do this in one package.

This can do what I want: http://www.mouser.com/datasheet/2/308/MC14532B-D-96716.pdf but if there is something with less inputs....
ledtester:
Use a priority encoder ic like a 74LS148 followed by a demultiplexer like a 74LS138.

Note that the '148 uses active low logic.
jhpadjustable:
That would be a priority arbiter.

Some details would be nice. What's the application? What are you optimizing for in this project? How fast does it have to be? What's wrong with the 4532 and what do you need instead?

I doubt you'll find that function in an orderable package, but you should review the compiled lists of 7400, 4000, and 74xG00 series logic, as on Wikipedia or elsewhere, just in case I missed one. You might be able to assemble the function out of only a couple of small packages using the 74xG series. If it doesn't have to work at several MHz (and honestly if you're using CD4000 series logic it probably doesn't) I doubt it takes all of 20 instructions in 8-bit machine code.
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