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ADG2188 usage

Hello,

I am planning to use ADG2188B device for video selection.

My requirement is as below.

I have 6 composite video inputs with SD-PAL/NTSC standard. I want to select any 2 videos based on my internal logic.

So I will connect X0 to X5 to input video sources. I will take the output from Y0 and Y2 to video decoder adv7182.

Again, I want to have the processed PAL/NTSC video to be duplicated from the board at the output.

I want to connect the video encoder adv7341 output to X7 and have the duplicated output @ Y5 and Y7.

The attached pdf represents the block level approach for my requirement.

Can you please suggest me, whether this approach will work fine?


Even for this approach, can I use single +5V supply or I should use +/-5V?

Also, I want to know how much current consumption will be there for this approach. If +/-5V to be used, then I have to select the appropriate inverting regulator for this IC.

Also, what should be the connection for unused ports?

Waiting for your quick response.

With Regards,

Hariprasad Bhat

ADG2188_crossbar_switch.pdf
  • Hi Hariprasad Bhat,

    I'll have a look on this. I'll get back to you soon.

    Regards,

    May

  • Hi Hariprasad Bhat,

    ADG2188 is a good choice for your application. It is a bidirectional 8x8 switch array with rows and columns can be configured as either inputs or outputs. The only concern that you may want to take a look at is that the array can be selected one at a time. You may not use X0 to X5 and X7 as the input at the same time. This is further explained at the Serial Interface Section, page 19 of the datasheet. Also, please see Table 7, page 20 for the Address Decode Truth Table of the device.

    For current consumption, 1uA is the max Idd consumption of the device which is stated on page 5 of the datasheet at Vdd=5V and Vss=-5V.

    For the unused pins, you may leave it floating so the channel will not add up in crosstalk.

    Let me know if this helps.

    Best Regards,

    May

  • Hello May Porley,

    Thank you for the response.

    Can you please comment on my following statements quickly?

    Datasheet; Page -18; Theory of Operation

    "The device is fully flexible in that it connects any X line or number of X lines with any Y line when turned on. Similarly, it connects any X line with any number of Y lines when turned on."

    With reference to above statement, I understand that I can connect a single input to multiple output. [ I consider X port as inputs and Y port as the outputs]

    In other words, X7 can be connected to both Y5 and Y7 simultaneously. [ I need to carry out 2 sequences of operation i.e. first connect X7 to Y5 and then X7 to Y7].

    For X0 to X7, I will connect for example X1 to Y0 and X4 to Y2.

    With regards,

    Hariprasad Bhat

  • Hi Hariprasad Bhat,

    Yes, you are correct for those statements. Also, you may want consider Table 7, Address Decode Truth Table of the ADG2188 datasheet for the sequence you need in your design.

    Let me know if you have other concerns.

    Best Regards,

    May

  • Hello May Porley,

    Let me summarize the discussion.

    • With ADG2188 device 6 input videos to 2 input selection in 2 separate lines is possible.
    • Video duplicate is possible, [Single input is duplicated in two outputs simultaneously ]
    • User has to configure the ADG2188 via I2C, in a  step by step sequence as per truth table mentioned in datasheet for above requirement [initially and dynamically].

    With Regards,

    Hariprasad Bhat

  • Hi Hariprasad Bhat,

    Yes, those statements are correct.

    Let me know if you have other concerns.


    Best Regards,

    May

  • Hi Hariprasad Bhat,

    As of the moment we do not have IBIS or SPICE models for ADG2188 yet but we are on the move in creating these. However, this would take a while.

    Let me know if you have other concerns.

    Best Regards,

    May

  • Hello May Porley,

    Thank you for you reply.

    Whether IBIS or Pspice models are available for the ADG2188?

    With Regards,

    Hariprasad Bhat

  • Hello May Porley,

    Can I use ADM8660ARZ part to generate -5V from +5V for ADG2188?

    With Regards,

    Hariprasad Bhat

  • Hi Hariprasad Bhat,

    The ADM8660ARZ can be used as long as it meets the specified power requirements of the ADG2188. So for as long as the ADM8660ARZ can generate +5V for Vdd and -5V for Vss then it can be used for your application.

    Best Regards,

    May