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Imagine you have some traces on a PCB, that connect from point A to point B. I would like to have control over that connection. I want to be able to enable/disable the connection from a distance (microcontroller included).

What is the best way to enable/disable the connection? Transistors, switches.... Something that the microcontroller can control, and that then can control the connection to the trace...

What is the best component to use for this purpose?

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    \$\begingroup\$ Depends what kind of signal this "connection" is supposed to conduct. \$\endgroup\$
    – Eugene Sh.
    Jan 14 at 21:53
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    \$\begingroup\$ There is no best way unless it is known what the connection carries. 16A at mains voltage, 5 GHz wireless LAN antenna signal, or something else? \$\endgroup\$
    – Justme
    Jan 14 at 21:56
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    \$\begingroup\$ What kind of data? Digital? Analog? How "high speed"? \$\endgroup\$
    – Eugene Sh.
    Jan 14 at 21:58
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    \$\begingroup\$ @user1584421 we still don't know what "high speed data transfer" means to you. \$\endgroup\$
    – Justme
    Jan 14 at 21:58
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    \$\begingroup\$ Looks like an XY-Problem \$\endgroup\$
    – Eugene Sh.
    Jan 14 at 22:13
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Without knowing anything about the signal, I'll say the most universal solution is an analog transmission gate. The signals must remain within the range of the power supply to the T-gate.

Depending on the signal characteristics, there are several simpler/cheaper options available. Can you describe the signals to be on these traces?

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  • \$\begingroup\$ Thanks. They are high speed data transfer digital signals. \$\endgroup\$ Jan 14 at 21:58
  • \$\begingroup\$ If you have supplies outside of the signal range, you could use MOSFETs. You just have to drive the gate at least one gate threshold above/below the max/min value of the signal (depending on type). \$\endgroup\$ Jan 14 at 22:08
  • \$\begingroup\$ Thanks. Since i don't know much about MOSFETS... What i should i research? I mean a good search term. "MOSFETS as a switch"? \$\endgroup\$ Jan 14 at 22:11
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    \$\begingroup\$ You need to be a bit more specific - are we talking about spi? If so, what bit rate? i2C? Or 8 bit parallel data? If you want a precise answer, give us precise information. Nevertheless, you might use multiplexers like 74HC157 or tristate buffers like 74HC244 or 245. These are good to probably 30MHz. If you need faster there are similar devices that are higher speed and can do voltage level translation. \$\endgroup\$
    – Kartman
    Jan 14 at 22:22
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    \$\begingroup\$ USB and Ethernet require very different solutions. Short of using relays, there is not really a generic solution. For USB, it would be uncommon to switch the signals apart from plugging it in and out. If you wanted multiple USB connections, you'd probably use a hub. Similarly with ethernet, but you'd probably use an ethernet switch chip. You might want to give us a concrete example of what you want to do. \$\endgroup\$
    – Kartman
    Jan 15 at 0:44

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