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24Oct/113

SBAMAT – ADG728 Module PCB Board

I did an update for the SBAMAT board.  This board is a breakout board for the ADG728.

The ADG728 is a CMOS analog matrix switch with a serially controlled 2-wire interface. It is an 8-channel matrix switch. On resistance is closely matched between switches and very flat over the full signal range. This part can operate equally well as a multiplexer, demultiplexer or switch array and the input signal range extends to the supplies.

 

If you need a neat analog mux this board is great for prototyping.  If you would like to build your own board the gerbers are here Gerbers SBAMAT.

Comments (3) Trackbacks (0)
  1. That layout makes me weep. The autorouter is not your friend. And the parts placement is terrible. For instance, C1 is a bypass cap… it is supposed to be close to the pin, not miles away. With it placed so badly, its likely introducing noise into the system rather than reducing it.

  2. This follows the same lines as your other post. Both of the projects are prototypes/development designs. They are by no means polished designs meant for high production. They are a Rapid Development approach using an auto router when possible and auto placement when possible. I needed a board to play with the ADG728 mix and this has fit the bill on many of my projects including repeater controllers, TM-710A keyboard adapter prototype, and a small test board for FSK switching. I appreciate your recommendations and if these designs were to be produced at higher volumes, better placement and more manual routing would be the way to go.

  3. Mostly my concern here was the bypass cap. That type of thing will lead to noise and problems with a circuit that can be hard to track down. It doesn’t take much time to place bypass caps beside their respective pins.

    Autorouting has its time and place. The majority of signals on a PCB don’t need an human hand to route them around for sure. Its prettier to do it by hand, but necessarily any better in terms of signal quality. The problem that I have with an autorouter in the hands of a beginner is that the autorouter can hide poor placement of components. If it was being routed by hand, it would be obvious that it was much harder to connect the pins than it should be and the components would naturally be moved into better positions. The autorouter glosses over all that.

    Anyhow, my intent was not to troll (despite my poor choice of words in my last post) but to help ensure that your future designs are better.


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