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Unread 10-04-2011, 12:52
Gdeaver Gdeaver is offline
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Re: Analog break out problem.

We built 2 robots identical. The competition robot used all this year parts. The practice bot used all last year parts. The Sharp IR conductive plastic problem had been resolved. It had no effect on what we saw this weekend. Both robots performed very well up to this weekend. Early on pre-ship practice the noise at most was not more than 3 or 4 buckets. It was not noticed at our first competition. At Philly, our robot was run under very, very high stress. Much greater than in practice at home or our first comp. This is when the issue really became apparent. The solution was to add the cap right at the analog break out port across V+ and GND. After that there was absolutely no bounce. We used 2 analog break outs. All the Sharp Ir's and ultra-sonic were on 1 break out. Noise was not an issue on this break out. All the Vishay sensors (981HE) were on the other break out and this is were the noise caused the problem. The Vishays are listed at 16ma max.
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