Dell Latitude 3540, Service Manual

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• USB 3.0/USB 3.1 Gen 1 RAIDs
• Optical Media Drives
• Multimedia Devices
• Networking
• USB 3.0/USB 3.1 Gen 1 Adapter Cards & Hubs
Compatibility
The good news is that USB 3.0/USB 3.1 Gen 1 has been carefully planned from the start to peacefully co-exist with USB 2.0. First of all,
while USB 3.0/USB 3.1 Gen 1 specifies new physical connections and thus new cables to take advantage of the higher speed capability of
the new protocol, the connector itself remains the same rectangular shape with the four USB 2.0 contacts in the exact same location as
before. Five new connections to carry receive and transmitted data independently are present on USB 3.0/USB 3.1 Gen 1 cables and only
come into contact when connected to a proper SuperSpeed USB connection.
Windows 8/10 will be bringing native support for USB 3.1 Gen 1 controllers. This is in contrast to previous versions of Windows, which
continue to require separate drivers for USB 3.0/USB 3.1 Gen 1 controllers.
Microsoft announced that Windows 7 would have USB 3.1 Gen 1 support, perhaps not on its immediate release, but in a subsequent Service
Pack or update. It is not out of the question to think that following a successful release of USB 3.0/USB 3.1 Gen 1 support in Windows 7,
SuperSpeed support would trickle down to Vista. Microsoft has confirmed this by stating that most of their partners share the opinion that
Vista should also support USB 3.0/USB 3.1 Gen 1.
USB Type-C
USB Type-C is a new, tiny physical connector. The connector itself can support various exciting new USB standards like USB 3.1 and USB
power delivery (USB PD).
Alternate Mode
USB Type-C is a new connector standard that is very small. It is about a third the size of an old USB Type-A plug. This is a single connector
standard that every device should be able to use. USB Type-C ports can support a variety of different protocols using “alternate modes,”
which allows you to have adapters that can output HDMI, VGA, DisplayPort, or other types of connections from that single USB port
USB Power Delivery
The USB PD specification is also closely intertwined with USB Type-C. Currently, smartphones, tablets, and other mobile devices often use
a USB connection to charge. A USB 2.0 connection provides up to 2.5 watts of power — that'll charge your phone, but that's about it. A
laptop might require up to 60 watts, for example. The USB Power Delivery specification ups this power delivery to 100 watts. It's bi-
directional, so a device can either send or receive power. And this power can be transferred at the same time the device is transmitting
data across the connection.
This could spell the end of all those proprietary laptop charging cables, with everything charging via a standard USB connection. You could
charge your laptop from one of those portable battery packs you charge your smartphones and other portable devices from today. You
could plug your laptop into an external display connected to a power cable, and that external display would charge your laptop as you used
it as an external display — all via the one little USB Type-C connection. To use this, the device and the cable have to support USB Power
Delivery. Just having a USB Type-C connection doesn't necessarily mean they do.
USB Type-C and USB 3.1
USB 3.1 is a new USB standard. USB 3's theoretical bandwidth is 5 Gbps, while USB 3.1's is 10 Gbps. That's double the bandwidth, as fast
as a first-generation Thunderbolt connector. USB Type-C isn't the same thing as USB 3.1. USB Type-C is just a connector shape, and the
12 Technology and components