Detangling USB-C, Part 3: Power DeliveryTopic: Chargers Portable Power Tech Specs
It’s no secret that USB-C and its associated specs are super confusing. Not all manufacturers are offering transparency, either. Even Google pro Benson Leung fell victim to a faulty USB-C cable that fried his laptop – yikes.
Part of the confusion stems from the fact that the Type C connector was announced at the same as the new USB 3.1 and Power Delivery specifications. But as we discussed in our last post, the C connector isn’t always bundled with the new specs, and having one doesn’t guarantee the other.
Benson’s unfortunate encounter is the result of what happens when USB-C cables can’t safely conduct Power Delivery. As of today, there aren’t many products on the market (besides the Google Pixel and Nexus 6 products) that include USB-C or this new spec.
But as we move toward the “one cable to rule them all” scenario, we’ll see a lot more Power Delivery devices come out. So let’s dive into this spec to see how it works, what makes it different, and what consumers can look for.
USB-A is so 2000-and-late: Power Delivery carries 4x the voltage of previous USB standards
Charging via USB has been limited to 5V since the USB 1.0 spec came out in 1996. Even as the data transfer speed increased through the 2.0 and 3.0 versions, supplying a lot of power was never really the main goal for USB. That’s why your printer, monitor, and other peripherals have always needed a wall plug for power and a separate cable for data.
The new Power Delivery spec increases voltage and amperage at the same time to 20V and 5A. That adds up to 100 watts of power — more than 10 times the previous spec. It’s enough to charge a laptop and a couple accessories simultaneously. And enough to cause damage if cables aren’t designed to handle it, which is what’s happening with faulty USB-C cables.
Power Delivery makes your USB-C cable work harder and smarter
Increasing voltage and amperage makes USB-C with Power Delivery work harder. But two key new features also help it work smarter.
On the charging side is what’s called varying voltages. With milestones at the 5-, 9-, 15-, and 20-volt marks, power can increase incrementally to meet the needs of the various devices that draw on a USB-C charger.
There’s also a feature called bi-directional power that lets devices give or take power based on battery needs. A monitor could power a laptop; a laptop could power a charging hub. Bi-directional power gives your devices discretion to negotiate how much power they give and take when they’re all connected.
USB-C with Power Delivery is behind the hype about “one cable to rule them all”
Because USB-C can do both data and power, there’s a chance we can get to a one-wire solution: Displays won’t need a power cable going into the wall and a data connection going to the computer (like you have now). That would all be replaced with one USB-C cable.
Of course, we always have to wait to see what the manufacturers do. But now that Power Delivery gives devices a chance to communicate through the USB-C cable, it can prioritize the messages sent through it.
Maybe some hubs come pre-programmed to make sure your laptop is powered first. Maybe others make sure your phone is top priority. At CES, Google showed off a dropdown menu in the Nexus 6P that lets you switch whether your phone gives or receives a charge. With that decision-making power, the future could mean you juice up a friend’s phone from yours when his battery is dying.
There’s a lot to get excited about then. Power Delivery is the driving factor behind USB-C’s coming changes to how our devices connect and communicate. But don’t go running to Amazon yet – it’s going to be a little while until USB-C cables and devices have full Power Delivery capabilities.
What to do now and what to do later
There are a few things consumers will want to look for when it’s time to stock up on Power Delivery gear.
First, manufacturers are starting to label everything with wattage, so make sure what you’re buying can provide enough wattage for the devices you’re trying to power. If you’re betting on manufacturers designing products that can be daisy-chained together – like a hub, laptop, and printer setup, you’ll need to tally up their wattage draw so that you can buy a cable rated high enough to support all three simultaneously.
The same thing applies to hubs. If you want to have laptop, phone, and monitor powered by one hub, you’re going to need a hub that has ample wattage to support those devices. Hubs can be especially tricky, because many of them available now supply 20W of power. But if your laptop is charging at 30W, you’re not going to have enough power to do anything else.
Lastly, keep in mind that not all USB-C cables are designed to the 3.1 and Power Delivery specs. And if you’re using a USB-A to C conversion cable, you can’t reach the maximum Power Delivery charge. Your setup generally has to be all C, all the time to hit max speed.
Power Delivery is going to be a big part of what gives USB-C its staying power and makes it a holistic technology solution. But we’re not there yet. If you want your USB-C fix, buy reliable cables and chargers with the 2.0 spec. Because it’s not worth destroying your current gear trying to get a step ahead.