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Fun With Diode Logic

A project log for Tern - Ternary Logic Circuits

A series of ternary logic gates and higher level components implemented in the real world.

mechanical-advantageMechanical Advantage 02/20/2016 at 08:240 Comments

I have started using pull-middle resistors here and there where appropriate and realized I hadn't ever tried these in combination with two-input diode gates. I already make common use of forward biased diodes with a pull-down to make a Max Gate and reversed biased diodes with a pull-up to make a Min Gate. Using forward biased diodes with a pull-middle gives this truth table:

Forward Biased, Pull 0

B

-

0

+

A

-

0

0

+

0

0

0

+

+

+

+

+

Using reverse biased diodes with a pull-middle gives this truth table:

Reverse Biased, Pull 0

B

-

0

+

A

-

-

-

-

0

-

0

0

+

-

0

0

Neither is of particular importance, but it's nice to keep that in my bag of tricks. The more gates I can make with fewer components the better. Sorry for the messy tables but not a lot of formatting options are available.

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