I'd like to test USB full speed with a goal of testing high speed (480 Mbit/s), I have a tek scope that does 300 MHz (which I could upgrade to 500 MHz) and I'm looking at a 500 MHz differential probe. As I understand it I also need a breakout board (which I'm not quite sure is the best thing to get), but I'm looking at this board from tek and one listed here.
What are the minimum requirements for a test like this?
Is this equipment list sufficient to preform an eye diagram test for full speed USB?
Is this equipment list sufficient to preform an eye diagram test for full speed USB if I have a 500 MHz scope?
Answer
What are the minimum requirements for a test like this?
Minimum requirements for test equipment to use for USB 2.0 signal quality evaluation is listed at USB.org in the following place. There are links that describe electrical test procedures and tool requirement for Rohde&Schwartz, Tektronix, Agilent, LeCroy, and Yokogawa oscilloscopes.
Typically the eye evaluation software tools are offered on scopes with no less than 2GHz bandwidth. For Tektronix, the eligible scope series are TDS7254/B, TDS7704/B, CSA7404/B, TDS6604/B, TDS6804/B, TDS6404, DPO7254, DPO7354, and DPO/DSA70000. The smallest eligible oscilloscope for USB 2.0 testing is MSO/DPO5204.
For FS eveluation you don't need differential probes, the scope does it mathematically using single-ended probes.
However, the software package can't be installed on smaller bandwidth scopes, so, even if 500 MHz bandwidth is OK for FS eyes, it is unlikely that you can use this scope.
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