USB Power Delivery (for Set top Boxes) - A dream so close and yet, so far away

Moving to the Set Top Box

On the Set Top Box world, things are still near square one. To start with, TVs equipped with USB-C power delivery are nowhere to be seen. For some reason, neither LG nor Samsung see any value on it. Apparently, those vendors see the few users connecting their flagship smartphones, which are today all using USB-C for both charging and output, not using the USB-C interface for output purposes, but any of the wireless versions instead.

Then there’s the issue of the lack of broad purpose. Contrary to PC screens, TVs have been extremely conservative on what regards to interfaces. Ever since digital high definition TVs where launched, the HDMI interface has been all but omnipresent. Even when presented with superior, more performing and cheaper alternatives, such as DisplayPort, HDMI remains the almost exclusive king of the TV interfaces.

The reason for this is not really simple, but it comes down to ensuring that there’s no user complains, although HDMI Forum is trying hard get get those complains. The logic behind the decision to stick to HDMI alone is based on the belief that HDMI just worksTM. Well, this was ever hardly true, at least as far back as HDMI reached version 1.2 and the advent of standard and high speed cables. Then, when HDMI came and barely offered 4K resolutions, using cable frequencies never really used before, users complained left and right on the lack of compatibility, not to mention the reduction of color rendering quality. Still, it’s simpler to ask the user to buy a proper HDMI cable, than to swap the entire TV.

On the DisplayPort side, this was never a problem, as additional and higher resolutions were always available before being needed ( Display port 1.4 which is available since 2016 already supported 60Hz 8K resolutions.

Problem 1: the Optionals

Both HDMI and DisplayPort are supported over USB-C, but neither of them is mandatory. This allows for a setup on which both ends are USB-C capable never to output any kind of image. From a user’s perspective, used to just worksTM, it’s a far cry. Not that on HDMI there’s absolutely no assurances that the entire setup would work at the intended resolution, but lowering the output resolution tends to solve all issues but the cheapest and lower quality cables.

Then, it’s not like HDMI forum is actually interested on the success of USB-C display interfaces. Evidence of this is the fact that even if USB-C does support HDMI transport, it arrived late and slow. HDMI was only added to USB-C alternate mode in 2016 and then only supporting HDMI 1.4 which limits it to 1080P resolutions.


In sum, having a TV set supporting USB-C is by no means an assurance that it supports either USB PD, nor HDMI over USB, which corresponds to a customer support worst case scenario.

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