Recently, the USB-IF Association released the latest USB PD3.1 fast-charging standard. The charging power has been increased from the original 100W to 240W, and it supports a maximum voltage output of 48V. It has received widespread attention in the industry for a while and has caused heated discussions.
Literally, USB PD3.1 can only be regarded as a minor version update of USB PD3.0, but in terms of power, this is a qualitative leap. What are the differences between USB PD3.1 and previous versions?
USB PD2.0
The USB PD2.0 fast charging standard was released in August 2014. It not only specifies the USB Type-C interface as the only standard interface but also gives this interface more functions, such as charging, data transmission, and audio transmission. In terms of charging, USB PD2.0 defines the support for 5V3A, 9V3A, 12V3A, 15V3A, 20V5A output, and the maximum charging power reaches 100W.
However, at that time, the Micro USB interface was popular, and the mobile phone market has basically been divided by private fast-charging protocols such as QC, AFC, FCP, and PE. It is difficult to popularize USB PD fast charging. This situation continued until 2015, when Apple released the industry’s first New MacBook equipped with the USB PD2.0 fast-charging standard. USB PD fast charging officially opened the way to popularization in the field of consumer power supplies.
USB PD3.0
In November 2015, USB PD fast charging ushered in a major version update, entering the era of USB PD3.0 fast charging. There are three main changes in USB PD3.0 compared to USB PD2.0: a more detailed description of the device’s built-in battery characteristics has been added; the device software and hardware version identification and software update functions through PD communication have been added, and the number has been added Certificate and digital signature function.
Simply put, from the point of view of charging parameters, USB PD3.0 and USB PD2.0 have not changed. They still support 5V3A, 9V3A, 12V3A, 15V3A, 20V5A output, and the maximum power is 100W. However, this update has not improved the chaotic situation of fast charging standards in the mobile phone market. The fast-charging standards are still separate and incompatible with each other.
USB PD3.0 PPS
In order to change the split of the fast charging protocol in the mobile phone market, the USB-IF Association released an important update to the USB PD3.0 standard in February 2017, adding a programmable power supply PPS on the basis of the USB PD3.0 standard.
PPS belongs to a type of Power Supply supported in USB PD3.0 and is a power supply that can realize voltage and current regulation using USB PD protocol output. The PPS specification integrates the current two charging modes of high voltage and low current and low voltage and high current. The voltage amplitude reduction is also the first gear of 20mV, which is only one-tenth of the QC3.0 standard at the time, and the adjustment is more precise.
And the USB-IF Association also reached a consensus with Thiel Labs, aiming to make the PPS fast charging standard unifies the fast charging technology. At present, PPS fast charging has become the fast charging standard with a very high share of the Android mobile phone camp. With the built-in charge pump of the mobile phone, it can realize high-efficiency and high-power fast charging, and models of many brands such as Xiaomi, Samsung, and Meizu are all in use.
USB PD3.1
USB PD3.1 is the fast charge standard just released by the USB-IF Association. The USB PD3.1 fast charge standard is actually an update based on the USB PD3.0 PPS fast charge.
The USB PD3.1 fast charge specification divides the power into two ranges, the standard power range (SPR for short) and the extended power range (EPR for short). The standard power range is currently the mainstream USB PD3.0 PPS fast charging standard on the market, and the maximum charging power remains unchanged at 100W; while the newly added 28V, 36V, and 48V voltages belong to the extended power range, and the three voltages correspond to The maximum output current is 5A, and the maximum output power can reach 240W.
In addition to three new sets of fixed voltages, the USB PD3.1 standard also adds three sets of adjustable voltage files (AVS for short) in the expanded power range, namely 15V-28V 5A, 15V-36V 5A, and 15V-48V 5A. The minimum step of AVS is 0.1V, and the PDP-based constant power limit mode continues.
Conclusion
Nearly ten years have passed since the development of the USB PD fast charging standard, during which it has also experienced many iconic iterations. Among them, USB PD2.0 is a fast-charging standard for real mass production and commercial use, and it also lays the foundation for realizing the unification of USB PD fast-charging. USB PD3.0 is more updated in terms of protocol recognition function, and the charging specifications have not changed.
The USB PD3.0 PPS fast charge standard has added a programmable voltage level, which is compatible with most private fast charge protocols and has become the most widely used fast charge standard in the Android mobile phone market.
USB PD3.1 is mainly to expand the scope of application of the USB PD fast charging standard. In addition to consumer products such as mobile phones and laptops, it can also be used in the field of monitors, servers, power tools, and security POE power supply. “Vision.
