WIP - PCB Design
Test points and designing for high-speed frequency
Basic takeaway is that for a PCB design you might want to insert pads on a trace to make it easier for the manufacturer to test the electrical characteristics of a certain node. Such pads can act as stubs with a parisitic capacitance to ground at higher frequencies. The test point should be close to the trace in order to avoid this.
Very dry tutorial of using an oscilloscope to test the quality of a high speed USB device
At 6:49 shows a bunch of tests that could be looked into further to learn more about what sort of tests you might do to characterize high-speed samples.
Additional information on signal-testing (USB 2.0-specific)
A way to look at ALL of the rising edges and falling edges for a given captured signal. They help you to identify lost packets and stuff like that.
Can be applied at the receiver OR the transmitter. You should try to collect eye diagrams from various points throughout the system in order to better diagnose issues.
If your eye diagram is fucked up it might be the transmission media, ESD, or external noise sources.
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