Gates - Basic question from new student

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To identify 'and' or 'or' gates in an electrical component, one would point to the silicon chip where transistors are patterned. These gates are typically not visible to the naked eye, as they are miniaturized on the chip. For visual references, users can explore resources like Wikipedia to see examples of integrated circuits and logic families. The 7400 series is a classic example of logic gates used in educational settings, with designations indicating civilian or military specifications. Understanding these components is essential for anyone studying Boolean logic and digital circuits.
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OK so I've been reading a lot about gates and Boolean logic lately and I understand how they function but if somebody were to open up the casing of an electrical component and they asked me to point to an 'and' or an 'or' gate what would I point to? Pictures would be very helpful thanks.
 
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Macwoni said:
OK so I've been reading a lot about gates and Boolean logic lately and I understand how they function but if somebody were to open up the casing of an electrical component and they asked me to point to an 'and' or an 'or' gate what would I point to? Pictures would be very helpful thanks.

You'd point to the little piece of silicon that all the leads are wirebonded to. It's just a couple of transistors patterned onto a tiny piece of silicon. (And no, individual transistors probably are not visible to the naked eye--I say probably because it depends on what process was used--hundreds of um used to be a fact of life)

But if you're looking for pictures, look down in this circuit.
http://en.wikipedia.org/wiki/Integrated_circuit
 
Thanks that helped me a lot!
 
this is what you would see in the olden days in school if you were breadboarding logic circuits. http://en.wikipedia.org/wiki/7400

notice that military-spec'd parts were also available in the 5400 series.

the 74 or 54 tells you that it is a civilian or mil logic family, and the next 2 or 3 digits the gate or function type. so a 5400 is a military quad 2-input NAND gate. and letters were added over time to accommodate newer gate technologies.

a classic and still excellent book on these old ICs is Don Lancaster's TTL Cookbook.
https://www.amazon.com/dp/0672210355/?tag=pfamazon01-20
 
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