Controlling 64 AV Inputs Plus Their Power Outlets

Projects General Guidance
1

Title: Controlling 64 AV Inputs Plus Their Power Outlets

Hello everyone,

With the help of Gemini and some internet research, I've put together this schematic to control 64 AV inputs and their respective power outlets, but I'd like the community's help to know if I'm on the right track.

  • 1 Arduino Mega 2560: To control the entire system.
  • 12 CD74HC4067 16-Channel Analog/Digital Multiplexers: To select the 64 AV inputs (64 / 16 = 4 CD74HC4067 for video, 4 for audio, and 4 for the power outlets).
  • 4 16-Channel 12V 10A Relay Modules with Optocouplers: To control the power outlets of the 64 AV devices.

My questions are:

Is this schematic feasible? Is there a better way to do this?

Sem tĂ­tulo
Sem tĂ­tulo1432Ă—854 381 KB

I appreciate any help and suggestions!

2

That is not a schematic, so no one can help. Have you tried even a small part of the design?

3

Thanks for the feedback. I'll get the parts, test, and post a schematic soon. Appreciate your patience.

4

The key here is to try it with a smaller setup. First one, then a full multiplexor, then the whole wack.

5

I doubt these chips have the bandwidth for analog video. I'm not even sure they have enough bandwidth for good quality analog audio!

Analog audio is an AC signal, which these chips cannot handle.

6

The datasheet indicates that the CD74HC4067 has an 89MHz bandwidth at 4.5V Vcc, exceeding composite video requirements. The low 0.051% sine wave distortion also suggests good audio handling. While AC signal handling isn't explicitly stated, the wide voltage range and low distortion imply compatibility.

7

If you look at, for example, the CD4052 (not 74HC4052 etc) it has a Vee pin. You connect a negative voltage to the Vee pin, which allows it to handle AC signals in the range between Vee and Vdd, so no DC offset required. I don't know if any of the 74 series chips have the same feature, but the one you chose does not as far as I can see. I suggest you explore the full range of analogue switches to find one suitable for your application. I have not checked the frequency response or other relevant characteristics so I can't comment on their suitability for you application. I believe, but I have not checked, there are analogue switches specifically designed for video.

8

Using the CD4052 will reduce the system's capacity from 64 devices to 20, but it might solve the issue. I'll conduct tests soon. Thank you

9

Consider looking into video multiplexers. You'll also need to match the impedance properly to maintain decent video quality. While your picture looks nice, it doesn’t provide much useful information because it’s not an annotated schematic (language of electronics). An annotated schematic would be much more helpful and would allow others to assist you more effectively.

10

VIDEO CROSSPOINT SWITCHES

11

To be clear I suggested the 4052 as an example, do explore the other devices in the same family. I'm not sure where you get 20 from, you can cascade them to get more outputs, as long as you can tolerate the increased insertion loss.

For example 8 off 4052 gives 64 outputs, add another one to the first 8 to bring that to 1 input to your A2D converter.

Don't take my word for it that this is the best choice, there might be other devices I'm not aware of that would do the job better.

12

After researching 'VIDEO CROSSPOINT SWITCHES', I found that the solutions are too expensive and not feasible for my project.

13

Thanks for the detailed explanation and suggestions. After further research, I've decided to proceed with the ADG1606BRUZ for my testing. I believe it aligns with the requirements of my project, especially regarding bandwidth and low distortion for the AV signals. I'll conduct the tests shortly and will return with the results. I appreciate your assistance.