What is the difference between fast charging and QC fast charging?

PD fast charging and QC fast charging are two commonly seen fast charging protocols. Since both are fast charging, what are the differences between these two?

What is the PD fast charging protocol? The full name of PD should be called USB Power Delivery Specification, which is a fast charging standard launched by the standardization organization of USB. USB-PD protocol, full name USB Power Delivery.

The reason why USB-PD is now gaining widespread device support is because it unifies the standards, so that in the future, it does not require the use of manufacturer exclusive charging equipment to quickly charge digital electronic devices. It unifies all low-power electronic device interfaces, making it more convenient for us to charge devices in the future.

So what is QC fast charging? Qualcomm has developed a set of fast charging standards called Quick Charge, abbreviated as QC fast charging. Qualcomm launched the first version of the QC fast charging protocol, QC 1.0, in 2013. In the most primitive 1.0 stage of QC fast charging, Qualcomm's fast charging solution also appeared simple and extensive: directly using a 10W charging power of 5V 2A. Currently, most smartphones on the market that use Qualcomm chips will support QC fast charging function.

In addition, the USB-PD protocol does not have the same relationship as other manufacturers' fast charging protocols, but rather includes and is included in the relationship. In the PPS (Fast Charging Technology Specification) released by USB-IF, the USB-PD 3.0 protocol already includes Qualcomm QC 3.0 and 4.0.