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Originally Posted by bigbop
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Yes, I know. At this time, both points are on the top of the PCB and only one is on the bottom. I hope I can find a second point on the bottom, close to the sync connector otherwise we will have to bring at least one wire around from the top to the bottom - or add a mini USB connector through a cutout in the case (yuck ). The problem with USB data lines is that they must be the same length or you end up with skew and you get lousy data throughput with lots of errors.
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Yes, I already dealt with this problem, that is the reason I had to build a second version of Aximizer: problems with USB hub. Those problems become critical, almost impossible to handle, when dealing with USB 2.0 signals, fortunately this is not the case (or I have to say: unfortunately
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For same reason it does not make much sense having only POS signal at the bottom area, it is supposed signal pair should go together for noise differential filtering.
If we have both lines at the bottom it should simplify the work a lot.
STF201-22 is same size like that one shown in the middle of your latest picture. An IC like that could be placed up side down at near clear area, stuck with epoxy and wired with that very thin wire used to fix broken board lines or when lines are cut during troubleshooting. Distance seems short enough for 1.1 signals, but still twisting lines will be a good prevention.
There is one problem about the USBH-P location, see the picture, white line shows where battery room starts. Some sort of very flat wire should be used.
I prefer the idea of having driver IC inside PDA if possible but, as I said at previous post, knowing where the lines are, hacking it can have several implementations :approve: