Especially in the fast charging of mobile phones, in the era of charging with gallium nitride chargers as the mainstream, when you buy a charger, you will always see such a sentence, supporting PD and QC fast charging. But just like these little friends, I only know it but I don't know why, it's written very clearly but I just don't understand what it means. So, today we will talk about these two issues.
QC and PD: a powerful alliance in the field of charging protocols
Here, in order to let everyone understand what QC is, I will add a little more. QC and PD are essentially a charging protocol. One of the indispensable parts of mobile phone charging is the power management chip (IC chip). The user uses the charger to charge the mobile phone, and the chip that controls the charging of the mobile phone is the "IC chip"; the other is the protocol for dynamically adjusting the current and voltage of mobile phone charging in the chip. That is what we call QC, PD protocol.
Before talking about PD, let's talk about QC first. After all, this big brother appeared earlier. Qualcomm is a leader in the field of mobile phone chips. Although the chips produced in the past two years are always called fire dragons, the performance is also really strong. In addition to wanting users to have more powerful performance, and also wanting users to have a faster charging efficiency, the traditional 5V/1A was upgraded to 5V/2A, and the speed was doubled, and the QC was officially opened ( Quick Charge) 1.0.
With this breakthrough, users can charge faster, and they want to be faster, and with the upgrade of USB technology, fast charging can continue to improve. In the QC2.0 stage, limited by the current that the MicroUSB interface supports up to 2A, Qualcomm chose a high-voltage, low-current method for the fast-charging solution. QC2.0 broke the conventional standard output voltage of 5V and raised the voltage to a level that can support up to 20V.
At this time, I have to mention the USB-IF Association again. Yes, it is the one with the USB interface that I introduced earlier, and it was named the one named thief. In addition to tinkering with the USB protocol, they also launched USB Power Delivery for fast charging, which is what we often call the PD protocol.
One of the main points to limit the power input of mobile phones is the USB interface. In 2013, USB-IF released the revolutionary TYPE-C 1.0 interface standard and USB-PD 2.0 standard. Qualcomm's QC 2.0 version was also released in the same year.
In contrast, the TYPE-C 1.0 interface standard has a super-dimensional upgrade under the PD protocol, which not only has traditional power and data transmission capabilities, but also audio and video transmission capabilities. Moreover, whether it is power, data, or audio and video transmission speed, it is better than traditional transmission lines. Compared with Micro-USB, the USB-C (USB Type-C) interface supports a maximum power transmission of 20V 5A, which is naturally more suitable for fast charging.However, after considering various aspects, mobile phone manufacturers mostly use high-voltage solutions of 9V and 12V, with a current of 2A, and a charging power of 18W or 24W.
The advantage of this solution is relatively simple for the user, and a conventional data cable plus a fixed high-voltage charging head can be used. But the problem is also very obvious. Since the high voltage of 12V cannot be directly used to directly charge the mobile phone, it needs to be decompressed to 4.2V that the mobile phone can support, which will cause the mobile phone to heat up, and part of the energy will be lost in it, and the charging efficiency can only be maintain the 80% level.
At this time, I have to mention the USB-IF Association again. Yes, it is the one with the USB interface that I introduced earlier, and it was named the one named thief. In addition to tinkering with the USB protocol, they also launched USB Power Delivery for fast charging, which is what we often call the PD protocol.
One of the main points to limit the power input of mobile phones is the USB interface. In 2013, USB-IF released the revolutionary TYPE-C 1.0 interface standard and USB-PD 2.0 standard. Qualcomm's QC 2.0 version was also released in the same year.
In contrast, the TYPE-C 1.0 interface standard has a super-dimensional upgrade under the PD protocol, which not only has traditional power and data transmission capabilities, but also audio and video transmission capabilities. Moreover, whether it is power, data, or audio and video transmission speed, it is better than traditional transmission lines. Compared with Micro-USB, the USB-C (USB Type-C) interface supports a maximum power transmission of 20V 5A, which is naturally more suitable for fast charging.
At this point in the development of things, Qualcomm obviously couldn't sit still, and quickly let itself enter the QC3.0 era. The change this time is to refine the voltage range, down to 3.6V, the highest voltage of 20V, and backward compatible with QC2.0. Due to the full use of the Type-c interface to replace the original MicroUSB interface, the maximum current has also been increased to 3A.
The USB-IF on the side saw that Qualcomm was so active, and he couldn't be at a disadvantage, and he quickly upgraded himself to the PD3.0 version. At this time, the technology of fast charging has become mature, which has caused the rapid charging standards of major mobile phone manufacturers at home and abroad to flourish, such as the follow-up Qualcomm QC 4.0/3.0, MediaTek PE3.0/2.0, Huawei Super Charge, Motorola Turbo charge, OPPO VOOC flash charge, OnePlus DASH flash charge, Meizu mCharge, etc. The whole situation is a situation of dominance.
In this era of promoting environmental protection, it is disrespectful for each household to use its own charging head. In this situation, Google, the father of the Android mobile phone system, has spoken to Qualcomm. If you want to use my system, you must support the PD fast charging protocol. With this shout, the unification of the charging protocol has since been opened.
In February 2017, the USB-IF organization released an important update to the USB-PD 3.0 standard, which added Programmable Power Supply (PPS) to the USB-PD 3.0 standard. The emergence of this set of standards can be said to have finally formed a fusion.
PPS expands the output voltage range of the USB interface from 5V to 3.0V~21V. The original high-voltage, small-current and low-voltage, high-current factions can be exposed to rain and dew under the embrace of PPS. The simplest example is that it can be used for almost all mobile devices. Fast charging, such as laptops, switches, etc.;
At the same time, the voltage range can be adjusted to 20mV, which can realize low-voltage and high-current direct charging; PPS has a pulsation mechanism to ensure the safety of the charging process. Since some mobile phones use high-current charging, more attention needs to be paid to safety. It is stipulated that at least every 10S, a pulsating communication should be maintained between the load and the adapter to prevent the charging process from running out of control.
Speaking of this, I think my friends should be able to understand what QC is. In terms of the relationship between the two, PD, as a USB-IF organization palm treasure, also masters the USB interface protocol, coupled with Google's requirements, it can be said that almost all domestic mobile phone fast charging protocols that use TYPE-C as the interface must support PD fast charging. Charge. The combination of PD3.0 and QC4+ has also become the standard for fast charging for a period of time, and the later QC5 has also entered the era of 100W fast charging following PD3.0.
Post time: May-03-2022