There is a big difference between PD charging and QC charging, that is, the voltage regulation of PD charging is 20mV, while that of QC charging is 200mV, which means that the voltage regulation of PD charging will be 10 times finer than that of QC. Considering the safety of voltage and current entering the battery, QC charging will be reserved, resulting in low efficiency of QC charging.
So PD charging will be more efficient than QC charging!
What is the reason that affects the charging speed? 30W charging is the output power of the charger, and PD charging and QC charging belong to two different charging methods.
In other words, it actually compares the effects of different charging methods on charging speed under the same charging power!
First of all, it should be pointed out that charging is related to many factors. For example, the selection of devices on the charging path, the routing impedance on the charging path, the efficiency of the charging chip, the battery capacity and the supported charging methods, and the adjustment of the charging strategy due to the influence of temperature during charging.
Matters needing attention in mobile phone charging 1. The maximum output power of the charger is not necessarily equal to the maximum power obtained by the mobile phone;
Generally speaking, the maximum output power advertised by the charger will be greater than or equal to the power obtained by the mobile phone. In order to pass the national safety certification, the maximum output power advertised by general chargers will be slightly greater than the power obtained by mobile phones.
2. According to the first point above, we can easily draw the conclusion that the maximum power obtained by the mobile phone is not equal to the maximum output power of the charger;
For example, Xiaomi 9 Pro uses a 40W limited power supply, but Xiaomi 9 Pro uses a 45W charger. Of course, one advantage of this is that you can charge the Xiaomi notebook, which is equivalent to a dual-purpose charger, which is convenient and practical!
3. Obviously, the charging power advertised by the mobile phone is not the power charged into the battery;
Related news USB-PD is a fast charging specification formulated by USB-IF organization and one of the mainstream fast charging protocols at present. USB-PD fast charging protocol is output by Type-C interface, but it cannot be said that USB-PD fast charging protocol must be supported by Type-C interface. USB-PD fast charging protocol can increase the power transmission through USB cable and connector, expand the power supply capacity of cable bus in USB application, so as to increase the charging voltage or current, and can freely change the power transmission direction. Type-C interface supports 15W (5V/3A) by default, but after implementing USB-PD protocol, it can support the output power of 100W (20V/5A) at the highest. So now many devices with practical Type-C interfaces will support USB PD protocol. PD charging is realized by communicating with CC pin of Type-C interface. In addition, it should be pointed out that the voltage adjustment step of PD charging is 20mV.