Preface
During the operation of the switching power supply, the power tube is responsible for charging the inductor in the closed state to store energy, and in the open state, the power tube is disconnected, and the inductor releases energy to realize the voltage conversion. In order for the inductor to release energy when the power tube is disconnected, a current loop is required, which requires suitable freewheeling components. According to the different selection of freewheeling components, it can generally be divided into two rectification modes: synchronous rectification and non-synchronous rectification.
Asynchronous rectification works by utilizing a Schottky diode, which produces a relatively large voltage drop when the current through the diode is large. Especially when the output voltage is low, the voltage drop of the diode accounts for a large proportion, so a large amount of power is consumed, resulting in low efficiency. In contrast, synchronous rectification technology uses MOSFETs with lower conduction resistance instead of diodes, which can significantly reduce the losses of the rectifier circuit, thereby improving the efficiency of the whole machine and meeting today's high-power fast charging needs.
The synchronous rectification controller that appears in this article
The charging head network has sorted out a number of application cases of 100-watt multi-port fast charging with built-in synchronous rectifier controller for the reference of readers and friends. Some of the parameters of the various chips that appear in the article are shown in the figure, and the following editor will introduce them to you in detail.
Huayuan Zhixin HY903
Huayuan Zhixin Semiconductor HY903 is a secondary synchronous rectification controller digital controller, support low-side synchronous rectification, no auxiliary coil, support DCM, CCM, frequency modulation and flyback operation mode, support 2.8-25V power supply voltage range, withstand voltage up to 120V. The high-current drive capability is suitable for a variety of synchronous rectifier tubes and is available in a SOT23-6 package.
Application examples
安克100W 2C1A氮化镓超能充
Anker's GaN Supercharger has folding prongs for easy storage and carrying. The charger has a 2C1A output interface, and the USB-C port supports 100W output power, and supports power blind plugging and automatic power distribution, which is easy to use. The USB-A port also supports fast charging, making it convenient to charge new and old devices. One charger is enough for simultaneous fast charging of laptops and mobile phones.
Related Reading:
Teardown report: Anker 100W 2C1A gallium nitride super charge
MPS MP6908A
The actual model of the silk-screen IBHJN synchronous rectifier controller is MP6908A, which comes from MPS Xinyuan Semiconductor, and the maximum working frequency is 600KHz. It supports DCM, CCM, QR, ACF multiple working modes, supports high-side and low-side applications, has ringing detection to prevent false turn-on, and adopts TSOT23-6 package.
Application examples
Greenlink 100W 3C1A GaN Charger
Greenlink's 100W GaN charger has a cube design, with fixed stamp pins, and is equipped with three USB-C and one USB-A port. Among them, the USB-C1 and USB-C2 ports both support 100W fast charging, which can meet the fast charging of laptops and mobile phone charging. The USB-C3 and USB-A ports support 22.5W fast charging and automatic power distribution.
Related Reading:
Teardown report: Greenlink 100W 3C1A GaN charger
Greenlink MFM certified 100W 2-in-1 gallium nitride charging station
This 100W desktop charging station launched by Greenlink is powered by a figure-eight cable, and the power cord of different lengths can be replaced according to the use occasion. The charging station has three interfaces of 2C1A, all of which support fast charging, which can meet the charging needs of mobile phones and laptops. The top of the charging station uses Apple's original magnetic wireless charging module, which is also very convenient for wireless charging of mobile phones.
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Teardown report: Greenlink MFM certified 100W 2-in-1 gallium nitride charging station
MPS MP6924A
The synchronous rectifier controller is from MPS, model MP6924A, is an LLC synchronous rectifier controller, with stronger anti-interference and fast shutdown function, and can be compatible with CCM/DCM mode. The MP6924A integrates two synchronous rectification controllers for the rectification application of the two secondary coil outputs of the LLC, which is suitable for the synchronous rectification application of the LLC converter and is available in an SOIC-8 package.
Application examples
ASUS 100W 2C1A GaN Charger
ASUS's 100W GaN charger features a white long body design with folding pins for easy carrying and storage, and the charger has a 2C1A triple output interface, which supports 100W power output when a single port output, and 65+30W output when used at the same time with dual ports, which can meet the needs of daily mobile phones and laptops at the same time, which is very practical.
Related Reading:
Teardown report: ASUS 100W 2C1A GaN charger
NXP TEA1995
The synchronous rectification controller from NXP, model TEA1995, has two built-in independent synchronous rectification drivers for the synchronous rectification of LLC architecture switching power supplies, with simplified peripheral components, supports 38V operating voltage, can meet the 28V output of USB PD3.1, and is available in an SO8 package.
Application examples
DJI 100W dual USB-C port GaN desktop charger
DJI's dual-port GaN desktop charger is designed with a split cable to adapt to applications of different lengths. The charger has 100W output power, supports 100W output for a single port, 100W output power for both ports, and supports automatic power distribution. In the actual test, the charger supports 5-20V 5A PPS fast charging, which can not only charge DJI products, but also meet the charging needs of mobile phones and laptops.
Related Reading:
Teardown report: DJI 100W dual USB-C GaN desktop charger
Jewalt JW7726B
The synchronous rectification controller of Silk Screen JWEWJ is from JWT, model JW7726B, supports CCM, DCM, QR and ACF modes, can effectively prevent the false opening of the synchronous rectification MOSFET during ringing, has fast shutdown capability to be compatible with CCM, can effectively prevent the gate gate from being coupled to the turn-on voltage during the start-up process (before VCC is established), supports high-side and low-side synchronous rectification applications, and is flexible to use.
The Jewalt JW7726B has a low quiescent current and an output voltage detection function for automatic switching of power supply. When the output voltage is higher than 4.6V, it is powered by the output voltage to reduce losses on the regulator. When the output voltage is below 4.5V, it is powered by the switch pin. The JW7726B is available in a SOT23-6 package with a compact set of peripheral components.
Application examples
Huntkey 100W GaN charging bar high-energy series W100
Huntkey Charging Bar W100 is based on three-dimensional fuselage design, and the front and top surfaces of the fuselage are tilted, which is not only small but does not occupy an area, and at the same time takes care of the user's plugging and unplugging experience. The top AC socket not only has a built-in safety door, but also adds a cushioning and protective pad, which is almost impossible to look at similar products on the market, and the details are in place. In addition, it is equipped with a USB fast charging port that supports up to 100W fast charging, which meets the fast charging needs of mainstream laptops and mobile phones on the market.
Related Reading:
Teardown report: Huntkey 100W GaN charging bar high-energy series W100
Summary of the charging head network
The charging head network understands that the synchronous rectification technology can use MOSFETs to replace the traditional rectifier diode, which greatly reduces the loss of the rectifier circuit, improves the switching power supply, and meets the design requirements of high-power and high-current fast charging adapters. In addition, the peripheral components of the synchronous rectifier controller are more streamlined and occupy less board space, which can meet the needs of fast charging with high power density.
With the continuous development of various electronic devices to intelligence and efficiency, the application of synchronous rectifier controllers in other fields will gradually increase. In addition to fast charging of mobile phones and laptops, they can also be widely used in many fields such as electric vehicle charging systems, industrial power supplies, and communication equipment power supplies to improve energy efficiency, reduce energy consumption, and promote the development of the overall industry in the direction of high efficiency.