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I'm using a 74HC4067 mux, which I want always enabled. Is it ok for me to simply connect the !E ("not E" or "inverted E") to GND?

To make the question more generic, is it ok to connect this "type" of input on the 74xxx components directly to GND or Vcc? For instance, to connect the !MR of the 74HC259 to Vcc.

Edit: Just to make the answer clearer, the original question was not mentioning that I meant connecting the !MR of the 74HC259 to Vcc. It could have been understood that I was wanting to connect it to GND, which would have always disabled it, as said in the accepted answer.

user1532080
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    Sometimes it's a good idea to connect such a signal to GND (or V+) via a resistor. That way you can pull the signal to the other level during testing, to verify disabling the MUX works. (Or to remove the resistor if you need to make design changes) –  Sep 26 '21 at 13:11
  • https://www.computerhope.com/jargon/j/jumper.htm : The middle pin goes to your chip. Others goto vcc/gnd through resistors. – Syed Sep 26 '21 at 14:14
  • @user_1818839 Thanks for the tip. – user1532080 Sep 26 '21 at 15:12

1 Answers1

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This answer was provided before the OP changed the question hence, my quotes below may seem to inaccurately reflect what appears to be written.

I'm using a 74HC4067 mux, which I want always enabled. Is it ok for me to simply connect the !E ("not E" or "inverted E") to GND?

Yes it is if by GND you mean 0 volts for the logic supply.

is it ok to connect this "type" of input on the 74xxx components directly to GND or Vcc? For instance, the !MR of the 74HC259

If you connect to GND (0 volts) then the 74HC259 will be held in reset. If that's what you want that's fine. Tie to Vcc if you want to enable it.

To make the question more generic....

I'm unsure why an enable pin being held low to therefore enable the device is generically related to holding a master reset pin low in order to keep the device disabled.

Andy aka
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  • You again! Thanks! Changed my question to make it clearer, I used the 74HC259 of an example of where one might want to connect directly to Vcc. – user1532080 Sep 26 '21 at 13:12
  • Changing the question after an answer is provided should only be done very carefully. I've now had to put a note in my answer so that people realize why my quotes aren't reflecting what you appear to have originally written. Nevertheless, not a big deal. – Andy aka Sep 26 '21 at 13:14