First of all I am new to electronics so i might use wrong terms.

What is this electronic component called or is it even a thing (Can it be bought)?

I have 10 input wires/channels for example. Only one wire is active at a time (5v).

The "multiplexer" output is the number of the active wire/channel.

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    \$\begingroup\$ perhaps a "priority encoder" \$\endgroup\$ – Peter Bennett Sep 11 '18 at 15:32
  • \$\begingroup\$ You might want to describe how your thing is different than an ordinary multiplexer \$\endgroup\$ – PlasmaHH Sep 11 '18 at 15:33
  • \$\begingroup\$ you ought to say logic inputs not just wires \$\endgroup\$ – Tony Stewart EE75 Sep 11 '18 at 15:34
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    \$\begingroup\$ en.wikipedia.org/wiki/Priority_encoder Peter is correct. \$\endgroup\$ – Tony Stewart EE75 Sep 11 '18 at 15:35

A digital encoder or Priority Encoder. They will often have \$2^n\$ inputs and \$n\$ outputs.

Additionally there will be an any-active output and an enable input.

You can combine multiple encoders together using these extra pins


Do you want a selected digital output to follow a digital input signal? Then demultiplexer is what you want, such as 74HC154


If you want to selected digital input to be fed to an output, then a multiplexer is what you want, such as 74HC150, altho they are not around anymore.

If you want an analog input/out to connect to a selected input/output, then an analog switch is what you want, such as DG406


If you wanted to read the state of 10 switches for example, a part like cd74hc4067 would be good. Connect the swithces to a pin and Gnd. Connect the common to something like an Arduino input with its internal pullup enabled. Then read the inputs one at a time - switches connected to Gnd would read low, switches that were open would read high. Thus 4 pins to select the switch, one input pin, to read 16 inputs.


Alternately two shift-in registers could do the same, and only use 3 pins, altho each input to the shift register would need its own pullup resistor. cd74HC165 for example



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