USB Power Delivery explained: What you need to know about ubiquitous charging (2023)

Robert Triggs / Autoridade Android

fast chargingit's a godsend when our gadgets run out of power. However, there are so many fast charging standards out there these days, making it difficult to choose the right charger for your smartphone, laptop or even external monitor. While most gadgets traditionally came with an adapter in the box, many manufacturers now require you to bring your own. Fortunately, USB Power Delivery (USB PD) is a universal charging specification that allows you to completely bypass the fragmented charger market.

USB power supply: what you need to know

Robert Triggs / Autoridade Android

USB Power Delivery is a common fast charging standard that can be implemented on all USB devices. In fact, USB PD has been around since 2012, around the same time the USB-C port was released. Before that, the only universal option was the (significantly slower) USB battery charging specification.

For starters, all USB ports support a very basic charge level of just 5V and up to 500mA, while more modern ports support 5V and 900mA of current. This builds on legacy support and is too slow to load all but most of the low power devices. The USB-C ports can be configured with 5V 1.5A and 3A for up to 15W of power, which is slightly faster but still quite slow compared to other fast charging standards.

USB promoters group

USB Power Delivery is much more powerful, supporting up to 240W of power to charge even the most demanding devices such as laptops. It's also safer, as the devices and chargers communicate with each other through the USB cable to confirm the optimal charging power. This handshaking approach supports voltage steps of 5V, 9V, 15V, 20V and above for output power from 0.5W to 240W.

The latest programmable USB Power Delivery (USB PD PPS) power standard also supports configurable voltages, allowing for optimal charging. If two devices cannot communicate a proper power rule, USB Power Delivery defaults to the next power option supported by the relevant USB protocol, such as USB-C 1.5A.

The latest USB PD revision can deliver up to 240W of power for demanding devices such as laptops.

USB Power Delivery is now commonly used to quickly charge smartphones, laptops and other devices. Examples include the entire line ofGoogle Pixeldevices and Apple's iPhone and MacBooks. Even Samsung'ssuper fast chargingit is based on USB PD PPS.

A wide variety of other smartphones also support the standard, often in addition to their faster proprietary standards. For example, many OnePlus smartphones support 18-27W USB PD charging. Is this in addition to the company's own Warp Charge orSuperVOOC from Oppotechnology.

USB Power Delivery versions compared

Robert Triggs / Autoridade Android

Now that USB Power Delivery has entered its third revision, the standard has been split into devices with slightly different capabilities. Although modern versions of the standard are compatible with older devices and chargers.

USB PD 1.0 was slightly simpler than the modern version. It simply offered six fixed power profiles for different categories of devices. This version only supports 10W (5V, 2A), 18W (12V, 1.5A), 36W (12V, 3A), 60W (12V, 5A), 60W (20V, 3A) and 100W (20V, 5 A) ). That's fine, but it's not exactly flexible for a wide variety of devices, including small smartphone batteries that prefer low-voltage charging.

More modern variants of USB Power Delivery 2.0 and 3.0 ignore fixed profiles in favor of more flexible power rules. These rules fix the voltage range, but allow for a wider range of negotiated current levels. The end result is a standard better suited to a wider range of devices. USB Power Delivery 3.0 also extends the communication protocol to support features such as battery status, enhanced security, and fast feature switching.

USB PD Programmable Power Supply (PPS) uitgelegd

Robert Triggs / Autoridade Android

Despite improvements with USB Power Delivery 2.0 and 3.0, they are still not fully suited to the flexible demands of very fast charging. The battery charging rate is sensitive to specific voltages and changes depending on the current battery charge. The defined voltages of 5V, 9V, 15V and 20V in the standard specification are not optimal for optimal fast charging.

The USB Power Delivery 3.0 revision, released in 2018, also introduced the Programmable Power Supply protocol into the standard. USB PD PSS is much more flexible and allows configurable voltage levels in very small granular steps of 20 mV. Combined with device-to-charger communication and voltage-controlled charging algorithms, the optimum voltage can be negotiated and even changed during charging. This makes USB PD PPS much better suited for fast charging than the standard USB PD protocol.

As the latest part of the standard, support for USB PD PPS in 2021 is limited to only a few charging gadgets and accessories. Support is starting to grow, especially in the charger market, but the latest spec is causing some headaches. . For example,Samsung Galaxy S23-serieit can only be fast charged at full 45W power using USB PD PPS chargers. Otherwise, consumers will be stuck with a slower 18W when using standard USB PD. The same goes for Google's Pixel series of smartphones.

How fast does USB PD charge?

Best Buy

Given the variable nature of USB PD charging and the wide range of battery capacities, it's impossible to give an accurate rate for the standard. In general, however, large battery capacity phones will be fully charged in just over an hour using the 18W USB power supply. For large capacity laptops with a 65W charge, it can take an hour or two.

Unlike laptops, smartphones generally don't like using high voltages to charge their batteries. Normally, the fast charging of smartphones uses 5V or 9V and high currents to charge the battery. For example, OnePlus' 65W charging tech uses 10V and 6.5A charging, and HUAWEI's 40W option uses a similar 10V and 4A. Please note that both are proprietary technologies.

9V is the closest USB PD voltage setting, which is limited to a much slower maximum power of 27W. Most of the USB Power Delivery smartphones we've seen don't use the full 3A either, limiting their power to 18-20W.

Proprietary technologies push the boundaries even further: OPPO offers 240W and Xiaomi already offers 120W charging. That said, there are diminishing returns in terms of power consumption versus charge time anyway. About 40 W is enough to charge a smartphone super fast.

Consumer convenience and the ecological argument

Ryan Haines / Autoridade Android

While charging speed is an important design factor for USB Power Delivery, and PPS in particular, it is not the primary design goal. USB PD was created as a single standard for powering a wide variety of USB devices. This reduces the need for your own ports, connectors and plugs.

First, this should make it much easier for consumers to simply plug in and charge. E-waste from old chargers and cables is a growing problem, not only for landfills, but also as a drain on precious metals and other finite resources. There are strong environmental reasons for both consumers and manufacturers to adopt a unified charging technology such as USB Power Delivery.

Smartphone brands removing charging pads from the case can be a controversial decision these days, especially since consumers don't necessarily own a compatible USB PD PPS charger. But in the long run, we might not think twice about the lack of included chargers, as all of our gadgets get fast charging from the plugs we already own. And if you want to buy a charger for multiple devices, you can always buy one.USB wall adapter with multiple ports. That's the theory anyway.