Re:USB 4 version 2 promises 80 Gbps speeds over existing cables
by londons_explore on Friday September 02, 2022 @02:52AM
(#32687447)
And 10,000 volts build up on your body when you rub a balloon on your head...
With high voltages, it's all down to how many joules you allow to be dissipated in a human. Ie. Current*voltage*time. Specifically, anything over about 0.01 Joules is dangerous. To use high voltages in a consumer product you need to limit either the current or the time, and you need to do it in a way that is very robust to being chewed on by a baby in a bath. And it needs to be robust to that even when built by a corner-cutting factory.
One approach to that is to have either end of the link 'test' the other end - ie. Simulate a human touching the wire. If power isn't turned off fast enough to be in spec, then the remote end or cable isn't working correctly and shouldnt be used.
With high voltages, it's all down to how many joules you allow to be dissipated in a human. Ie. Current*voltage*time. Specifically, anything over about 0.01 Joules is dangerous. To use high voltages in a consumer product you need to limit either the current or the time, and you need to do it in a way that is very robust to being chewed on by a baby in a bath. And it needs to be robust to that even when built by a corner-cutting factory.
One approach to that is to have either end of the link 'test' the other end - ie. Simulate a human touching the wire. If power isn't turned off fast enough to be in spec, then the remote end or cable isn't working correctly and shouldnt be used.