[ts-7000] Re: USB serial reset

["Jesse Off" <>]

> I don't see any major decoupling around the USB connectors on my board.

5V is decoupled on the board with a 47uF cap before the polyfuse.  Its
really up to the USB device for anything after the fuse.  Keep in mind
that you can't just put a large cap and expect to solve the problem. 
The cap needs to have a reasonably low ESR, otherwise you'll need
multiple caps in parallel.

The majority of USB devices we're probably tested on PC's with large
200-400 watt power supplies (vs your 10 watt 5V supply), the engineers
that designed your USB device probably never thought to decouple 5V on
the device itself and are in-effect somewhat violating max current
draw  on the USB device, if only for a few microseconds. 

//Jesse Off




 
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