Usb-IF Association in May 2021 released the USB PD3.1 fast charging standard, in terms of power, USB PD3.1 fast charging up to 240W charging, and added 28V, 36V, 48V five sets of fixed voltage, which further expands the scope of application of fast charging technology. Soon after, Apple launched the first USB PD3.1 fast charger that supports 140W output power, followed by several third-party fast charging source brands such as Flash Pole, Yajingyuan, New Sibao, and Ruijiada, accelerating the popularization of high-power fast charging technology.
The emergence of high-power fast charging has brought a new circuit design, the most obvious change is that there are more PFC circuits in high-power fast charging sources, especially in the high-power fast charging source products sold in China, PFC circuits are an indispensable part. As the core of the PFC circuit, the PFC chip has ushered in a stage of rapid development.
High-power power supply must be PFC
PFC is a power factor correction circuit used in a charger to boost the rectified voltage and then power the flyback or ACF or LLC primary through capacitor filtering.
In general, more than 75W chargers need to increase the PFC circuit, which can solve two pain points; the first is to take care of the low-voltage input and use a larger capacity primary filter capacitor, which will occupy a considerable part of the volume of the charger, and the volume increases, making the charger inconvenient to carry. The second is a large capacitive capacitor, which presents a capacitive load when the alternating current is charged for the capacitor through the rectifier bridge, generating a large inrush current, causing pollution and interference to the power grid.
For the sake of volume and grid, the capacitor in the high-power charger cannot be selected according to the formula of 2μF/W for the low-power charger. Using a boost PFC boost circuit, the rectified voltage can be boosted to about 380V for primary power. While reducing unnecessary capacitance, it also eliminates the interference caused by large capacity electrolytic capacitors to the grid.
According to the statistics of charging head network, at the upcoming 2022 (Spring) USB PD & Type-C Asia Conference, dozens of fast charging source chip OEMs will be welcomed, among which Mao Ruixin, Jingfeng Mingyuan, PI, Biyi Micro, Silicon Jie, Jiehuate, Silan Micro, Tongjia Technology and other enterprises have already laid out the PFC chip product line in advance for high-power fast charging.
At present, the common PFC controller on the market can be divided into two types, one is an independent PFC controller, such products are more flexible in application, in LLC, ACF, QR three mainstream power architecture can be used; the other is the PFC boost controller and primary controller integrated into a chip, the more common is the PFC + LLC chip, the advantage of this type of controller is that it can simplify the circuit design and achieve higher efficiency, two-in-one also meets the requirements of high integration of the charger.
It is worth mentioning that as a third-generation semiconductor material, gallium nitride power devices and silicon carbide diodes have a wide range of applications in PFC circuits, of which gallium nitride power devices are mainly used as boost switches, and silicon carbide diodes are mainly used for rectification after boost. The combination of silicon carbide and gallium nitride can increase the switching frequency of PFC boost from less than 100KHz to more than 300KHz, greatly reducing the volume of the boost inductor and improving the power density of the adapter.
At the same time, the high-frequency performance of silicon carbide diodes, without the characteristics of reverse recovery, can also reduce switching losses and improve conversion efficiency, in addition to being used in high-power fast charging sources, it can also be used in PC power supplies and outdoor power supplies.
At this exhibition, 14 gallium nitride power device original factories such as Nano Micro, Innosec, Juneng Chuangxin, Gallium Future, Transphorm, Xinguan Technology, Nenghua, etc., as well as basic semiconductors, Tyco Tianrun, Meipusen, Sen Guoke and many other original silicon carbide factories were unveiled, and brought the latest product technology.
High-power PFC chip summary
The application scenarios and product classification of PFC chips are introduced above, and the following continues to share a detailed introduction of some of the PFC chips that will be unveiled at the 2022 (Spring) USB PD & Type-C Asia Conference.
Booth C40-C41 and C54-C55: Shanghai Jingfeng Mingyuan Semiconductor Co., Ltd
Jingfeng Mingyuan introduced a high-PF, low-harmonic boost PFC controller BP2628, which can be used for PC power supply, USB PD charger and medium and high power LED driver power supply.
Jingfeng Mingyuan BP2628
The Crystal Fung BP2628 supports critical continuous mode or discontinuous mode, which can achieve zero current shutdown of diodes, helping to improve conversion efficiency and reduce electromagnetic interference. The chip supports switching frequencies up to 540KHz, and can be used with gallium nitride switch tubes and silicon carbide diodes to reduce the inductor volume at high frequencies and realize high-frequency and small-volume boost PFC circuits.
Jingfeng Mingyuan BP2628 operates in critical continuous mode during heavy load, which can reduce the conduction loss of the switch tube and improve the conversion efficiency; enter the intermittent mode at light load, reduce the switching loss, and maintain the output voltage stability while ensuring good PF value and input current harmonics.
Jingfeng Mingyuan BP2628 has built-in and perfect protection functions, including cycle-by-cycle overcurrent protection, output overvoltage protection, chip power supply undervoltage protection, feedback pin short circuit protection, chip internal overheating protection and other protection functions to ensure the reliable operation of the system. At the same time, the feedback pin short-circuit protection function can be used for PFC-level switching control to reduce the standby power consumption of the system.
Booth B29-B30: PI
The veteran power chip brand PI has launched a PFC control chip, which can be applied to USB PD fast charging, PC power supply, LCD screen power supply and other fields.
PI PFS7628C
The PI PFS7628C is a PFC chip with integrated 600V switching tube, integrated 600V MOSFETs and diodes, which can provide high power factor and high efficiency under wide load conditions, and has built-in perfect protection functions. Provides stable and efficient power factor compensation with an output power of 110W.
DETAILED SPECS OF PI PFS7628C.
Related Reading:
1. Disassembly report: SATECHI 100W 2C1A Gallium nitride fast charger
2. Disassembly report: RAVPOWER 90W dual USB-C port PD fast charger
Booth B47-B48: Shenzhen Biyi Microelectronics Co., Ltd
At present, Biyiwei has launched a total of 7 PFC control chips.
Biyi Micro KP2801
Biyi Micro KP2801 is a highly integrated step-up PFC constant voltage controller, the chip adopts a quasi-resonant working mode, while the active power factor correction control technology can meet the requirements of different inputs, high power factor, ultra-low harmonic distortion and high efficiency under different loads.
KP2801 internal integrated degaussing signal detection technology At the same time, the 650V high-voltage start-up and power supply circuit is integrated, eliminating the need for auxiliary winding detection demagnetization and power supply, and requires few peripheral components, which greatly simplifies the design and production costs of the system.
The KP2801 integrates complete protection functions to ensure safe and reliable system operation, such as VDD undervoltage protection function (UVLO), cycle-by-cycle current limiting (OCP input undervoltage protection function (BOP), overtemperature protection (OTP) output overvoltage protection (OVP), etc.
1. PFC+QR controller is fully domestically produced, and The 120W gallium nitride fast charging scheme of Biyi Micro has made its debut
2. Biyi Micro launched KP2801 quasi-resonant boost PFC controller
Biyi Micro KP1511
Biyi Micro KP1511 is a highly integrated step-up PFC constant voltage controller chip using quasi-resonant working mode, while active power factor correction control technology can meet the requirements of high power factor, ultra-low harmonic distortion and high efficiency.
KP1511 has integrated degaussing signal detection technology, and integrates 650V high-voltage start-up and power supply circuits, eliminating the need for auxiliary winding detection degaussing and power supply, requiring few peripheral devices, greatly simplifying the system design and production costs.
The KP1511 integrates complete protection functions to ensure safe and reliable operation of the system, such as VDD undervoltage protection function (UVLO), cycle-by-cycle current limiting (OCP) overtemperature protection (OTP), output overvoltage protection (OVP), output undervoltage protection (UVP), etc.
Booth A03: Silicon Jie Semiconductor Technology (Hangzhou) Co., Ltd
Silicon Jie has launched a total of two PFC control chips SY5072 and SY58874V, mainly used in high-power AC-DC power supply, LED lighting, fast charging and other fields.
Silicon Jay SY5072
Silicon Jay introduces the SY5072 critical mode boost PFC controller, which uses constant on-time operation to achieve high PF values, and quasi-resonant switches for high efficiency and improved EMI performance. Specially designed to enable fast start-up and highly reliable protection functions to meet safety requirements.
Silicon Jie SY5072 adopts valley bottom opening to reduce switching losses, reduce the switching frequency at light loads, and improve light load efficiency. Built-in high output current MOS tube driver, support switch tube overcurrent protection, built-in transition optimization. The device supports protection measures such as overvoltage, overcurrent, and overtemperature protection.
Silicon Jie is available in a small SOT23-6 package that complies with RoHS and is halogen-free. The external components are streamlined to enable a compact PFC design, reducing the proportion of the PFC stage in the power supply.
The Silicon Jay SY5072 supports 150W of output power, and built-in transition optimization provides better linear transition and load transition. Suitable for AC-DC switching power supplies, pre-stage two-stage switching power supplies and LED lighting applications.
1, built-in gallium nitride chip, small size and high power, Xiaomi 120W USB-C fast charge disassembly
Silicon Jay SY58874V
Silicon Jay SY58874V is a boost PFC converter, the chip built-in boost MOS tube, with high PF, the use of quasi-resonant switch to improve conversion efficiency and better EMI performance, support output overvoltage protection, peripheral devices streamlined.
Booth A09: Jevate Microelectronics Co., Ltd
In view of the application needs of the high-power fast charging source market, JW1571 has launched a PFC control chip JW1571.
J. Wat JW1571
The JW1571 is a constant voltage controller with high voltage accuracy in an SOP8 package. Suitable for single-stage boost power factor correction (PFC) applications. A constant on-time control strategy ensures high power factor, eliminates the need for input voltage sensing circuitry, simplifies system design, and saves losses; critical on-mode operation reduces switching losses, improves EMI performance, and greatly improves efficiency.
The JW1571 features multiple protection features that greatly improve system safety and reliability, including VCC UVLO, CS overvoltage protection, FB overvoltage protection, and overtemperature protection.
J. Wat JW1962O
The JW1962O is a constant voltage controller with high voltage accuracy for single-stage boost power factor correction (PFC) applications, with a constant on-time control strategy that ensures high power factor without the need for input voltage detection circuitry, simplifying system design and saving losses. Critical conduction mode operation of the chip reduces switching losses, improves EMI performance, and greatly improves efficiency.
The JW1962O has multiple protection functions that greatly improve the safety and reliability of the system, including VCC UVLO, ISP overvoltage protection, open feedback protection, FB overvoltage protection, and overtemperature protection.
Booth B62: Hangzhou Silan Microelectronics Co., Ltd
SilanWei has launched three PFC controllers, which can be mainly used in the fields of lighting power supply, TV power supply and high-power power adapter.
Silan Micro SD7528
The Silan Micro SD7528 is a high-performance, critical-on mode power factor correction (PFC) controller with integrated high-performance linear multiplier that reduces distortion of AC input current.
The Silan Micro SD7528 controls the output voltage through an internal voltage mode error amplifier and a precise internal reference voltage. The chip consumes very low power, with a maximum of only 15μA before start-up and less than 5.5mA of current during operation. An internal integrated enable function controls the shutdown or opening of the circuit, while an effective two-step overvoltage protection module is integrated to safely handle overvoltage states that occur at start-up or when the load is disconnected. The SD7528 optimizes control for better light-load THD and PF performance.
Booth B73: Tongjia Technology (Shenzhen) Co., Ltd
At present, Tongjia Technology has launched a PFC controller for high-power power supplies, which can be mainly applied to LCD screen TV power supply, PC power supply and other fields.
Tongjia LD7593DA
The Tongjia LD7593DA is a voltage mode PFC controller operating in conversion mode with a variety of integrated protection functions such as OVP, OCP, and internal OTP.
The Tongjia LD7593DA is available in a SOP-8 package with a conversion mode for power factor correction. High efficiency and low switching noise are achieved by zero-current switching. Induced AC input voltages are inducted to compensate for OCP and PF values between high and low AC input voltages.
Charging head net summary
In order to achieve the purpose of "everything can be charged", the USB-IF Association has achieved a comprehensive upgrade to the charging protocol, and the power of the charger is also increasing. In addition to charging power is greater, charging speed is faster, high-power fast charging source can also be combined with a secondary buck circuit to achieve multi-port output, with a power supply to meet the charging needs of multiple devices. It is foreseeable that high-power fast charging will gradually become the mainstream of the future market.
In addition, the CURRENT LLC, ACF and QR control technologies used in high-power fast charging sources are very mature, and gallium nitride and silicon carbide power devices have also achieved large-scale applications. The biggest feature of these PFC controllers introduced this time is that they are flexible in application, can be used with different types of power main control chips, and form a high-performance power supply scheme that meets the requirements of safety regulations, and accelerate the mass production and listing of high-power fast charging products.
The upcoming 2022 (Spring) Charging Asia Exhibition, which will be held from March 23 to March 25, will invite companies that appear in the article to display and share, and welcome to the booth to communicate.