What's difference of USB PD2.0, USB PD3.0 and USB PD3.1?

What's difference of USB PD2.0, USB PD3.0 and USB PD3.1?

Since its initial introduction, USB PD fast charging technology has undergone multiple significant iterations, from PD 2.0 to the current PD 3.1, each upgrade delivering more efficient and safer charging experiences to users. This article will provide a brief introduction and comparison of three common USB PD charging standards.

USB PD 2.0, as the officially released fast-charging standard for mass production and commercial use, not only designates the USB Type-C interface as the sole standard port but also enhances its functionality to include charging, data transfer, and audio transmission. PD 2.0 defines charging parameters supporting outputs of 5V3A, 9V3A, 12V3A, 15V3A, and 20V5A, achieving a maximum charging power of 100W. The introduction of this standard laid the foundation for the unification of USB PD fast charging. Although the mobile phone market was still dominated by proprietary fast-charging protocols like QC and AFC at the time, PD fast charging began to gain widespread adoption in consumer electronics with the release of the New MacBook by Apple.

USB PD 3.0 is an upgraded version of PD 2.0. Compared to its predecessor, PD 3.0 does not introduce significant changes in charging specifications, still supporting 5V3A, 9V3A, 12V3A, 15V3A, and 20V5A outputs with a maximum power rating of 100W unchanged. Its primary improvements lie in the protocol layer, including more detailed descriptions of built-in battery characteristics, the addition of device software/hardware version identification and software update capabilities via PD communication, as well as the incorporation of digital certificate and digital signature functions. These enhancements strengthen protocol security and interoperability between devices, paving the way for future PPS functionality. Although PD 3.0 lacks breakthroughs in charging specifications, it lays a crucial foundation for the development of subsequent fast-charging protocols.

USB PD 3.1 is the current fast-charging standard, representing a significant upgrade from PD 3.0 PPS. It divides power into two categories: the Standard Power Range (SPR) and the Extended Power Range (EPR). The SPR retains the 100W limit of PD 3.0 PPS, while the EPR introduces three fixed voltage tiers-28V, 36V, and 48V-with a maximum output current of 5A per tier, enabling up to 240W output. Additionally, PD 3.1 incorporates three adjustable voltage tiers (AVS) within the EPR: 15V-28V 5A, 15V-36V 5A, and 15V-48V 5A, with a minimum voltage step of 0.1V for enhanced precision over previous versions. The release of PD 3.1 signifies the expansion of the USB PD fast-charging standard from consumer electronics to broader application scenarios, including monitors, server tools, and security PoE power delivery, further realizing the vision of "all things being chargeable.".

Below table show the detail comparison.