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For devices that demand
more power, USB Power
Delivery (or USB-PD) is
able to increase power
transfers up to 100W by
varying voltage (up to 20V)
and current (up to 5A). The
veryȴrst version of the spec was released in mid-2012,
but everything sort of fell into place recently thanks to
the USB Type-C connector standard. The ability to have
bidirectional powerȵow and both USB and non-USB
signals over the same reversible connector/cable is key to
convincing larger device makers (e.g., gaming console and
monitor makers) to adopt USB-C and USB-PD.
Because USB-PD is a separate protocol/hardware
solution, it’s up to device makers to support it. Put another
way, if your device has a Type-C port, don’t assume it’s
capable of USB-PD.
The conȴgurable voltage and current of USB-PD has also
led to many people thinking that USB-PD is the same as
some of the popular proprietary fast-charging technologies
out there, such as Qualcomm’s Quick Charge. This is
simply not the case. Using Nintendo’s Switch console
(which supports USB-C and USB-PD) as an example, the
console will not charge at the optimal speed if you use
a Quick Charge adapter. What you really need is - you
guessed it - an adapter that explicitly supports USB-PD.when the phone tried to pull too
much power than what the port was
capable of.:KRōVWREODPH"
When such incidents happened, it’s
human nature to point ï ngers. Did
the USB-IF do a poor job deï ning the
USB-C spec? Did the cable makers
cut any corners? Was the user at fault
for not doing enough research before
buying?hook up our existing devices stuck
with legacy ports with new purchases
that use USB-C, we’ve to rely on
things like USB-A-to-C or microB-
to-C adapters and cables.
And herein lies the problem: many
cables with a USB-C plug on one end
and a legacy plug on the other end
are not properly built.
You see, as simple as they may
look, USB cables have plenty of
engineering smarts in them. They
all have resistors that, for ease of
explaining, relay information about
the power source’s capability to the
device that’s drawing power. In the
aforementioned cases of electronics
failing, the culprit was always
the USB-C-to-A cable. In Benson
Leung’s case, he got a completely
miswired cable. For Dieter Bohn, his
cable packed a wrong 10k pull-up
resistor (when it should have been
56k), so his laptop’s USB port blewMAY 2017 | +:0 85