Re: USB2517: ESD protection and filtering
Thanks for your feedback.
The device I connect is a smartphone, pretty sure it -can- drain more than 500mA.
Maybe my understanding of USB protocol need some investigation but here's what I thought: on connection, during the enumeration and negociation, the device is considered as low power or high power, thus providing 100mA or 500mA. Based on this assumption, the device could not drain more than 500mA. Am I wrong with this ?
I made a test with the USB2517 EVboard and a Klein Tools ET910 (not the most accurate, but for a test I guess it is OK)
- loading one port with a test load to drain 500mA, the current drained is about 460mA and oother ports are still available and usable
- loading one port with the very same cable and smartphone, the current drained is about 430mAand other ports are still available and usable
About the OS, on Windows 10, I have noticed something: on the device I am reviewing, when the USB hub goes down, even resetting the hub doesn't make it back "alive": it appears as "other device" with a yellow interrogation mark. Unable to test it on Linux but it seems Windows is unable to re-enable the port.
For the choke and ESD protection, it is then good practices