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I am going to be working in a project involving logic gates and would like to start practical testing. However, I cannot seem to find anywhere transistors that match typical Boolean operations. While I know I can reproduce any logic gate from simpler ones, I would like to focus on the logic of the circuit and not worry about recreating all the gates.

I will be utilizing these in conjunction with an arduino, and am expecting a circuit voltage of either 5v or 3.5v. I also need these to be breadboard friendly.

Gates I am thinking of:

AND OR NAND NOT etc

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    \$\begingroup\$ It sounds like what you want to buy are packaged logic gates rather than individual discrete transistors. Most people today would use the 74HCxx or 74HCTxx series (for example 74HC00 is four NAND gates), but there's also the older 74LSxx, both of which are available in either surface mount or breadboard-compatible DIPs. There are also various smaller surface-mount-only devices that contain just a gate or two instead of the traditional four or six. \$\endgroup\$ – Chris Stratton Mar 23 '18 at 15:40
  • \$\begingroup\$ digikey.com/product-detail/en/texas-instruments/SN74LS08N/… for example. \$\endgroup\$ – vini_i Mar 23 '18 at 15:43
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Real logic gates look like this:

enter image description here

You need to hook up Vcc and ground, the 74HC series would be a good place to start. Make sure you understand logic switching levels.

Get DIP packages for breadboards.

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  • \$\begingroup\$ ah yes. Forgot these existed since my electronics class back in college. Thanks! \$\endgroup\$ – Snappawapa Mar 23 '18 at 16:38
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You seem to be confusing logic gates and transistors. Logic gates are made from transistors.

Transistors don't "match typical boolean operations". Other than basic inversion, it takes multiple transistors to implement boolean operations.

Nowadays, you rarely do boolean operations in dedicated logic anymore. You do all that in the microcontroller. The micro then controls external things directly, after all the decisions have been made as to when something should be off or on.

Basically, use the firmware to implement "logic operations". Then use transistors as switches to control external devices.

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    \$\begingroup\$ I consider this a sad development that raw gates are no longer used to implement small-medium projects. There is an art in making things simple and sturdy. For this specific project, I need the gates due to the (lack of) speed of the Arduino controller to sense inputs. \$\endgroup\$ – Snappawapa Mar 23 '18 at 16:41
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    \$\begingroup\$ You're listing microcontrollers as the preferred and only way of implementing logic gate functions? That function's for PLDs (CPLDs, FPGAs), with microcontrollers an option in relatively slow systems. Downvoting, I'm afraid. \$\endgroup\$ – TonyM Mar 23 '18 at 16:53
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    \$\begingroup\$ @Tony: I didn't mean to say microcontrollers are the only way. I mention them specifically because the OP said he is using a arduino, which has a microcontroller at its core. For anyone asking such a basic question, and probably not even really understanding what he has all that well, FPGAs are too advanced. Bringing up things like CPLDs would just add confusion. Remember, this is a guy that thinks individual transistors can implement boolean operations. \$\endgroup\$ – Olin Lathrop Mar 23 '18 at 20:09
  • \$\begingroup\$ @Snap: There is nothing sad about technology advancing and giving us better options than we had previously. Using several discrete logic chips when the functions can all be performed in a single microcontroller that is already there anyway is hardly making it "simple". That's more complex, larger, and therefore most likely less sturdy. \$\endgroup\$ – Olin Lathrop Mar 23 '18 at 20:14
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Here is a 3-input NAND

schematic

simulate this circuit – Schematic created using CircuitLab

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