av murgatroyd » 2015-09-18 14:39
Nja, det gäller USB 3.1 och Type C connector etc:USB Power Delivery: how do 100 watts sound like?
At the time of its conception, USB was expected to be a vessel for carrying data, not power. That's why USB 1.x and USB 2.0 were capped at a humble 2.5 watts (0.5 amps at 5 volts) – enough to charge a compatible cell phone, but not always sufficient to power something bigger, such as an external hard drive. Then came USB 3.0 and bumped the output to 4.5 watts (0.9 amps at 5 volts). That's a much more acceptable figure, but today's mobile gadgets can easily take at least twice as much juice when charging up their batteries. Thankfully, the USB folks have developed something to address the situation. It is called USB Power Delivery.
USB Power Delivery co-exists with current USB 2.0, 3.0, 3.1, and USB Type-C specifications. It is a different thing, however. USB PD specifies five power delivery profiles – up to 100 watts in scale – applicable over a USB connection while data is being transferred. Technically, there's six of these profiles, but the so-called Profile 0 is "reserved" and doesn't do much at this time. So, here are the five that matter:
Profile 1 - 5V @ 2A, 10W (Default start-up profile)
Profile 2 - 12V @ 1.5A, 18W
Profile 3 - 12V @ 3A, 36W
Profile 4 - 20V @ 3A, 60W
Profile 5 - 20V @ 5A, 100W
Läs mer på http://www.phonearena.com/news/All-you- ... WXmpZyK.99
'Audiophile in hibernation'
