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Sorry for dumb question, I'm really newbie in electronic.

As I wrote in topic, What's the name of this circuit? Dose the circuit has any specific name at all ?

enter image description here

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    \$\begingroup\$ It doesn't have a name. Just something someone made up. \$\endgroup\$
    – Lior Bilia
    Jan 9 '19 at 19:29
  • \$\begingroup\$ It's a NOR gate. \$\endgroup\$
    – user253751
    Jan 9 '19 at 23:06
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The overall diagram probably doesn't have a name. It shows two LEDs that are always going to light up together; if you were designing something systematically you probably wouldn't duplicated like that.

(Of course duplication is sometimes what you want. A circuit to systematically duplicate a given signal probably does have a name.)

The individual components you're looking at are NAND gates. It's a neat fact that any logic gate can be built from NAND gates.
For example if you feed both inputs with a single signal (as happens several times in your diagram) then you've made a NOT gate.
Put a NOT gate on each of the inputs of a NAND and you've built an OR gate, which is what the first half of the diagram shows.

If we ignore the duplication that's happening at the end, then what we're looking at is a NOR gate made out of NAND gates.

Such patterns might be useful if you want to keep a very narrow inventory of bread-board components, or you have a super-refined process for etching one single kind of gate into a silicon wafer.

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    \$\begingroup\$ I believe that back in the 1990's, there was a flavor of ASIC that was just a sea of NAND gates; the customer got to specify one or two mask layers to connect them up into a logic chip. \$\endgroup\$
    – TimWescott
    Jan 9 '19 at 21:53
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    \$\begingroup\$ A possible reason for the final gates in that circuit would be for additional drive current -- although if you're really driving an LED from a logic chip you should have a current-limit resistor in there someplace (not to mention a VCC or ground connection). \$\endgroup\$
    – TimWescott
    Jan 9 '19 at 21:55

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