Fast Charging Protocols
The fast-charging field fully illustrates the phrase “one mountain is always higher than the other” when the 65W is still fresh in our minds, the 90W is the best. The new Lenovo Legion has popped up, and that’s not all, Xiaomi then has a new 120W device that’s 3C certified.
The fast-charging leader Oppo/Vivo two companies naturally will not be left behind, Vivo announced in August will have a 120W With the new phone, OPPO went a step further and released 125W of fast charging technology.
The speed of fast charging in the past two years is really beyond the expectations of us ordinary people. However, in the face of many VOOC, QC, SCP, and other fast-charging new words, I do not know if you have not dazzled, take this opportunity to us! Let’s talk about the wide variety of protocols in the fast-charge.
What is the fast charging protocols?
First of all, what is the protocol? To use a simple analogy, it’s like a code, and both parties hold the same code to establish contact.
Going back to the phone, it represents the power management ICs integrated inside the phone and charger, respectively, when the phone and charger are connected via the data cable. When the two ICs are connected, they will coordinate with each other for the most suitable voltage and current, and the fast charging will only be activated after mutual authentication and “handshake”.
When activated, the power management IC also adjusts the output and input voltages and currents according to the protocol, which is the charging protocol. The role, different charging protocols, the control strategy for the charging process, all have some differences.
Private Fast Charging Protocol
It’s the protocols that make the different fast-charging protocols not fully compatible with each other, with most phones only using their charging heads. To achieve the fastest charging speed, we call this situation “private protocol”.
There are many different types of private protocols, the best known being OPPO’s VOOC Flash Charge. The VOOC flash charge is compatible with the OnePlus WARP, realme DART charge, and other flash charges. The charger is universal. Vivo’s FlashCharge speed is also quite good, but the compatibility is not as good as OPPO, and can only be used on its machine.
Huawei’s Fast Charge Protocol is divided into FCP (Fast Charge Protocol) and SCP ( (Super Charge Protocol), the former is used more in the early days, belongs to the genre of high-voltage fast charging. The main focus is now on SCP, which is currently supported up to 40W and is also only supported on its machines.
Xiaomi’s fast charging is special, as it uses a magic PD protocol and adds CC contacts, which make it support PD fast charging, require a special charging cable and charging head. So, the Xiaomi Fast Charge is also only for home use.
These are just the common private protocols that are incompatible with each other, making it necessary for consumers to purchase charging devices with more be careful, to prevent this kind of fragmentation, the market needs a common fast-charging standard, which is where the “public protocol” comes in.
Most of the manufacturers with private protocols on the market today are also compatible with some public protocols, allowing for the use of the same charger with different brands.
Public Fast Charging Protocol
There are several public protocols on the market today, the common ones being Qualcomm’s Quick Charge fast charging, MediaTek’s Pump Express, and PD Fast Charging.
However, before these fast-charging protocols, there is also a basic public protocol called BC 1.2 (Battery Charge 1.2). According to the dedicated charging port (DCP) mode, this protocol can provide up to 7.5W (5V1.5A) of charging power. For the current battery capacity above 4000mAh, this speed naturally can’t keep up.
Qualcomm’s QC Quick Charge is believed to be familiar to many people, and it is a representative of high-voltage fast charge. It was first launched in 2013 when the highest power was 10W (5V2A). By QC 3.0, the power has been further increased to 36W, and it supports 200mV step voltage regulation, which is no longer a fixed set of voltage and current.
Qualcomm calls it the intelligent regulation optimal voltage (INOV). QC 4 supports step voltage regulation down to 20mV and current adjustment of 50mA. At the same time, support for USB PD+PPS is added. The subsequent QC 4+ is mainly backward compatible with the old QC 2.0 and QC 3.0, and some security features have also been added.
In addition to Qualcomm, processor manufacturers MediaTek has also introduced a fast charging protocol called “Pump Express”, or MTK PE for short. At present, few manufacturers use it except Meizu. In the early days, like Qualcomm QC, it was a kind of high-voltage fast charging. Since PE 3.0, low-voltage fast charging was adopted, and it also incorporated the USB PD 3.0 PPS standard. At present, the fast charging protocol has evolved to PE 4.0, and the current can reach up to 5A.
As the USB standard maker, USB-IF (USB Developer Forum), of course, will not sit idly by. They hope to introduce a fast charging protocol that supports a wider range of devices. This is PD fast charging (USB Power Delivery). Relying on the CC line in the Type-C interface, it can be compatible with mobile phones, tablet computers, and notebooks. The current maximum power can be up to 100W.
PD fast charging is currently the most extensive charging protocol. Since the popularization of USB-C and Google’s strong promotion, more and more mobile phones, tablets and laptops have begun to be compatible with this protocol.
The universal type can be said to be the strongest currently. At present, there are commonly USB PD 2.0, USB PD 3.0, USB PD 3.0 (PPS), the former two belong to high-voltage fast charging, and the PPS of the latter belongs to a branch of PD 3.0, which is called Programmable Power Supply. It incorporates Qualcomm QC, MTK PE, FCP, VOOC, and other fast charging protocols, and supports 20mV and 50mA step adjustments, and the current adjustment is more accurate.
PD charging seems to have a trend of unifying rivers and lakes, does this mean that we can buy a charging cable that supports the PD protocol to support fast charging of various brands in the future? Obviously not. At present, whether it is mobile phone manufacturers that support PD or QC fast charging, most of them support charging gears with lower public protocols.
Besides, many private fast charging protocol technologies are now ahead of public agreements. If you want to enjoy the highest speed fast charging, you have to rely on your private protocol. At least, the idea of using all the fast charging devices in one line is temporarily difficult to realize in the interests of various manufacturers.
Source: WHYLAB
