Three Reasons USB Type-C is Confusing

Ok so you got your new phone, realizing that its got USB Type-C, but then you can’t plug it into your type-C dock to get an HDMI output, what gives?

Apparently it must support something called “Alt Mode”. Quoting from Benq (USB-C Introduction: What is USB-C DisplayPort (DP Alt Mode) | BenQ US)

Given the confusion over USB-C DisplayPort, the next logical question is “How do I know if my device supports DisplayPort over USB-C?”. There is currently no standard way to identify a USB-C DisplayPort directly on the device, and some brands don’t even bother printing the DisplayPort logo on the ports that support it for their products. The best method to decipher whether your device supports DisplayPort over USB-C is to check either the product specs on the manufacturer’s official website or to check websites with in-depth product reviews and/or information. Within those sites you’ll be able to find detailed breakdowns of each port on the device.

Most of the time, Type-C Ports supporting HDMI will have at least USB 3.1 Gen 1, like the Galaxy Tab S9 and iPad Pro M1. But this doesn’t mean that the new iPhone 15 will not support DP Alt Mode, this post from All iPhone 15 Models Support DisplayPort for Up to 4K HDR Video Output to External Display – MacRumors says that it does. However, things like USB-Power Delivery (USB-PD) won’t be guaranteed to be supported. Even my Samsung Galaxy A70 does not support 65W PD, only Samsung’s 25W Super Fast Charging.

There’s also the case of Thunderbolt, but that’s for another.

So what’s the most sure way of knowing that your phone supports DP Alt Mode?

• Samsung’s flagship phones and tablets support DP Alt Mode, search for “Wired Dex”
• Most other flagship phones like the Vivo X80 and Xiaomi’s 13 Ultra

In general, if GSMArena says that the USB section contains “Displayport”, you’re good to go.

Cheers!