Control a Multiplexer


I am trying to automate the switching of my Multiplexer using some device. I need inputs to the control switches as 000011 or 0101010 or 00110011.

Could you recommend what device can I use for the generation of these binary outputs which then connect to the MUX control switches ?

Thank you

Welcome to the forum!

The values you show are different bit lengths, (6, 7 & 8).

Should they have all been 8-bit values with leading zeros (00000011, 00101010, 00110011) or does this mean the unused bit positions need to be high impedance (xx000011, x0101010, 00110011)?

The solution for those two distinct problems are very different.

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Does anyone have a suggestion for this customer? I wasn’t sure about the different bit lengths, either (the other reply).

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No its for switching the MUX , so it continues unless stopped. Which means it goes like 000011…000011 until its stopped manually. Am currently planning to order the AG1012 waveform generator to control the MUX but I was told it won’t be helpful.

If I connect a BCD counter, would I be able to control the MUX ?

the switching time needs to be 1 ms and the MUX I am using is this :

Please let me know how I can go about this.

Thank you in advance :slight_smile:

Hi tde022,

So I took a look at the BH76362FV, which is a video signal switching MUX. It has 6 input video channels, one output video channel, and 4 digital control lines. It is a 4-bit mux, and depending on the values of the CTLA, CTLB, CTLC, and CTLD, the MUX will send one of the 6 input channels, Mute, or Standby to the output.


I don’t know how a waveform generator could be used to control this video mux. A BCD counter could not control this because it does not count high enough, as it wraps around to zero from nine, but most of the required values are above 7 (value of MSB, CTLD, must be high except for Standby mode). A binary counter could be used, but half of the values (0 - 7) will give the same output - Standby - and I presume you’ll need something to read the value back so you know which input is selected.

I don’t know what you mean by switching time. What is your input device?

It would seem like a microcontroller would be the simplest device to control the MUX. It could read whatever input you fed it (rotary encoder, multi-position mechanical switches, serial data, etc.), set the control pins accordingly, and provide some sort of feedback to the user to indicate which input or mode is selected.


I am sorry for the confusion. I sent the wrong link for the MUX. I will be using the following MUX :

it is an 8:1 MUX of which I will be utilizing 6 channels. I have also attached the entire circuit diagram of which this MUX is a part of.

I think I might have confused you as well with the bits. But I need single inputs from each control pin and not the entire values of number above 7. If you see the truth table below for the MUX, you will understand why I mentioned 001100 … this is not as an entire number but first input is 0 then 1 then 0, just so that as per the truth table the MUX switches.

Now can I connect a sq wave generator along with a counter ?

And if still a microcontroller would be a better idea… which one would be the best ? I was thinking on terms of Arduino nano… but I am open to suggestions…

That’s a 3 bit system and the codes are sequential. You only want to count from 0 to 6 (000 to 110) so a basic count up and reset at 7 (111) setup should work. Counter can be either binary or BCD since the range is less than 10.

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With the 74LV4051, you could cycle through the three control bits and have it clear back to zero with a BCD or binary counter and reset after 7, as Paul states. However, using a function generator as your counter clock input to accomplish this seems unusual, as you would need to slow it down to 2Hz or less to be able to select a desired channel without it behaving like a roulette wheel.

If this is to be more than a bench experiment, then, yes a microcontroller would seem more suitable (and probably even then). Pretty much any microcontroller with sufficient I/O should work for this application, so you should use whatever type you feel most comfortable with.

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Alright. I will try working with Arduino Nano since I am comfortable with it. I will update you when I get the output. Thank you so much for the assistance. It was really helpful :+1: :pray: :smiley:

I have one more question… In a waveform generator, there is an option of high peak/low peak instead of amplitude/offset. What does that mean ?

This is the waveform generator I am using.

I am not certain, but based on the context of this being an arbitrary waveform generator, and because you imply that this is an alternative to “amplitute/offset”, I would say that it is another way of specifying the maximum and minimum output voltage of the signal produced. If you have an asymmetric (arbitrary) waveform, it would seem to be easier to characterize it this way than to give an amplitude and offset.

That’s my guess.