Half Adder Challenge

Thread Starter

TTLMaster

Joined Jun 20, 2014
3
I have recently made a simple half adder circuit using TTL and RTL logic. The circuit totals 13 components (8 resistors and 5 transistors) minus the logic inputs and outputs, ground, and Vcc. I want to see if any other users can make a working half adder using less components. That is my challenge to you.

P.S. For my circuit simulator, I downloaded it from here:
http://www.falstad.com/circuit/
 

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Thread Starter

TTLMaster

Joined Jun 20, 2014
3
Thank you for your submission. Unfortunately, the circuit simulator I have does not have Schottky diodes. So, for all intensive purposes, I used normal diodes in the place of the Schottky ones.

The circuit now has 11 components (6 resistors, 3 transistors, and 2 diodes).
 

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Thread Starter

TTLMaster

Joined Jun 20, 2014
3
I ended up solving the problem myself. Unfortunately, LEDs have to be used since in the XOR Gate, it is only a logic HIGH when current passes through it. But anyways, here is the final circuit I have come up with. The circuit has 2 LEDs, 3 resistors, and 6 diodes. It uses diode logic rather than diode-transistor logic. Since it uses diode logic, it is not practical to combine to make larger circuits, but it is very simple.
 

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