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Substitute for priority encoder? Answered

Hey,
    My project requires the implementation of a priority encoder.All the other gates that form the remaining circuitry are CMOS whereas the only priority encoder that is available to me,is a 74ls147 which uses TTL.The part where TTL interlinks with CMOS turns out to be extremely finicky and doesn't seem to work after several failed attempts using transistors in between and powering the CMOS chips with voltages such that the 'high' voltage was the same for both TTL and CMOS.The only option I had was to go for an ic (don't remember the part number) that acts as a portal between CMOS and TTL .But that would mean an additional ic  and so,I figured that I could probably develop my own version of a priority encoder(sort of..because it's not exactly a 'PRIORITY' encoder) with a quad 2 input xor gate and a triple 3 input or gate ics,tailored specifically to meet the needs of my project.I haven't tested it on breadboard yet and would like to know your opinion.The circuit diagram and the truth table has been attached as a picture.
Thanks for spending your valuable time to read my question :D

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steveastroukBest Answer (author)2015-06-07

The Z gate does nothing, unless you want to buffer Sensor 4

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user

Yes,I wanted it to be buffered and besides ,the 3 input or gates come as triplets.Why not utilise all the three?

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Adarsh_tronix (author)2015-06-16

Or by 'IT' , do you mean the buffer ?

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