With the overall popularity of Type-C interface, the consumer charging industry has also ushered in A comprehensive reform. The time utilization requirements of human are becoming more and more efficient, and the charging time requirements of electronic products are becoming shorter. The original uneven data cable interfaces, such as USB-A port and Micro USB port, are gradually replaced by Type-C. In the face of numerous chargers and charging protocols on the market, there are still quite a few consumers who are not clear about how to choose the best charger for their devices. A PD charger is a power adapter with the PD protocol. In this article, I will start with the data interface, charging protocol and several commonly used power chargers to help you choose the best charging device for your own.

1. The difference between USB interfaces

• Generally, the PD power adapter has two interfaces, the USBA interface and the USBC interface. The USBA interface transmits low power while the USBC interface transmits high power. From the perspective of function definition, the core function of PD power adapter is PD fast charging. In the era of fast charging, the definition of power adapter is no longer as simple as the traditional power adapter. Different customers have different logical requirements for multi-port control. In addition, there are different display and control modes. And when it comes to customization, that's what MCU has traditionally been strong at, supporting the diverse needs of its customers.
• PD Fast charge is A kind of charging protocol belonging to USB TYPE-C interface, which can only be used for USB type-C interface. QC3.0/QC2.0 protocol can be used for our common Android Micro-B interface, USB-A interface and USB type-A interface, and can also be USB type-C interface.
• The USB-DCP protocol is released by USB-IF (USB Implementers Forum, a non-profit USB standards development organization).
• At present, most of the USB interfaces available on the market are the following four types: USB-A, Micro USB, Type-C and Lightning. A USB-B interface may appear on the printer.
• This port used to be used for USB sticks, phone and tablet chargers.
• Micro USB, which is a standard on Android phones a few years ago, is also called "Android port" by many people in daily life. Currently, mobile phone manufacturers have been basically eliminated.

2.fast charge communication identification is inconsistent

• PD fast charging is not identified by the communication protocol D+ and D-. Note: PD fast charging is not identified by the communication protocol D+ and D-. PD fast charge is identified by CC PIN communication.
• QC3.0/QC2.0 is identified by D+ and D- communication protocols. Micro-B is also designed to distinguish the two fast charges. In the USB type C interface, we know that there are also D+ and D-PIN pins. USB type C can be made into PD fast charge and QC fast charge dual-compatible products. Micro-B and USB TYPE A can only use QC3.0 or QC2.0.
• PD is Power Delivery, which means power transmission management in Chinese. PD charging protocol is a power transmission protocol published by USB-IF organization. USB-Power Delivery can improve the type-c interface to 100W.USB-PowerDelivery is one of the mainstream fast charge protocols. The mainstream fast charge protocols form the fast charge specification formulated by the USB-IF organization. The USBPD increases power delivery through USB cables and connectors, expanding the power supply capacity of the cable bus in USB applications. This specification can achieve higher voltage and current, up to 240W, and can freely change the direction of transmission.

3. Charging power difference

• PD Fast charge is a charging protocol of USB Type-C interface and can only be used for USB Type-C interface. Generally, fast charge can be used for a variety of interfaces (Micro-B, Type-A, and Type-C). The specified input current for the Micro-USB interface is 1.5A, rather than 2A, the QC 1.0 fast charge standard introduced by Qualcomm. At that time, the current transmission limit of 5-pin Micro-USB commonly equipped with Android models was 2A, and the consensus of the industry was to reserve a certain margin to ensure charging safety, so the normal charging current of most models was 1.5A and the charging power was 7.5W (5V 1.5A). QC 1.0, on the other hand, simply increased the charging current to 2A, increasing the charging efficiency of the smartphone by one-third from 7.5W.
• Each brand promotes its own unique way of fast charging, such as Huawei, MI, oppo, VIVO, APPLE, Samsung and so on. Finally, it can be said that there are only PD and QC two fast charging modes. In addition, QC can also be said to be a branch of PD. Chargers that support PD quick charge can charge phones that support QC quick charge, while chargers that support QC quick charge cannot charge phones that support PD.
• The charging stage of fast charging can be divided into constant current precharging (small current), constant current fast charging (large current), constant voltage charging (current from large to small until the completion of charging), whether high voltage and low current (QC belongs to this type) or low voltage and high current, it is necessary to adjust the input voltage of the power adapter through the USB-C interface.
• QC3.0/QC2.0 fast charge is the earliest high voltage fast charge protocol, and the charging power is generally 18W. PD fast charge is the most complete fast charge protocol at present, with the maximum power supported up to 240W. The common power is 18W. 30W, 45W, 60/65W, etc.

4. The difference between power supply equipment and application equipment

• QC3.0/QC2.0 application devices such as: mobile phone, mobile power, such as 18W power around with USB port lithium battery charging equipment.
• PD fast charging has DFP (power supply mode), DRP (power supply/device two-way mode), and has the unity of USB interface function, high power and other characteristics. The range of application devices is very large. (such as mobile phone charger, tablet charger, laptop charger, large capacity battery charger, etc.)