Preface
Recently, the charging head network got a fast charging plug-in board launched by Xiaomi, which is not only equipped with 6-bit AC jack and 2C1A three USB interfaces, but also supports Xiaomi's private flash charging protocol, which is very friendly to users of Mi products. Not only are there many holes, but the price of the product Jingdong flagship store is only 99 yuan, which can be said to be quite good. The reputation of Xiaomi plug-in board products has always been very good, and the following charging head network will disassemble this product to see how the workmanship materials are.
Xiaomi 67W fast charging plug-in board unboxing
The Xiaomi 67W fast charging power strip comes with a power cord, and the plug-in board and body are designed in gray and white contrast, and the overall design style is simple.
The power cord has a three-pin plug with a large top edge for easy plugging and unplugging.
The connection between the cable and the fuselage is protected by a rubber sleeve.
The top of the power strip is equipped with a main switch, an indicator light, a 6-position jack and three USB interfaces of 2C1A.
The indicator light on the side of the main switch prompts the user whether to power on or not, which is intuitive and clear.
The AC jack has a built-in safety door, which can effectively prevent foreign objects from being inserted into a single hole and ensure the safety of electricity.
The bottom four ends of the fuselage are equipped with non-slip pads, and the product parameter information is printed on the shell.
Close-up of product parameters
Model: CXB6-3QM
技术参数：2500W MAX，10A MAX，250V~
USB输入:200-240V~,50Hz,1A MAX
USB总输出功率:67W MAX
Single-port output:
USB-A:5V3A、9V2A、12V1.5A 18W MAX
USB-C1：5V3A、9V2.22A、12V1.67A 20W MAX
USB-C2:5V3A、9V3A、11V6.1A、12V3A、15V3A、20V3.35A 67W MAX
Dual Port Output:
USB-C1+USB-C2：20W+45W
USB-C1+USB-A：15W
USB-C2+USB-A：45W+18W
Three-port output:
USB-C2+USB-C1+USB-A：45W+15W
Manufacturer: Qingmi (Beijing) Technology Co., Ltd
The product has passed CCC certification.
The measured length of the power cord is about 160cm.
The length of the power strip body is about 21cm.
The width of the fuselage is 83.58mm.
The thickness is 28.48mm.
Feel the size of the power strip in your hand.
In addition, the weight of the product was measured to be about 446g.
使用ChargerLAB POWER-Z KM003C测得USB-C2口支持FCP、AFC、QC3.0/QC5、PD3.0、PPS、DCP、Apple 2.4A充电协议。
PDO报文显示USB-C2口还具备5V3A、9V3A、12V3A、15V3A、20V3.25A五组固定电压档位,以及5-11V5A、5-20V3.25A两组PPS电压档位。
测得USB-C1口支持FCP、AFC、QC3+、PD3.0、DCP充电协议。
PDO报文显示USB-C2口还具备5V3A、9V2.22A、12V1.67A三组固定电压档位。
测得USB-A口支持FCP、AFC、QC3+、DCP、Apple 2.4A充电协议。
Xiaomi 67W fast charging plug-in board disassembly
Remove the screws to open the bottom housing.
The internal AC jack part adopts an integrated copper strip design, and the high-quality copper conducts electricity quickly and dissipates heat well.
The PCBA module is fixed with the housing using screws, and the back is covered with a heat sink.
The PCBA module is taken out, the heat sink is separated, and a thermal pad is attached to the corresponding core heating device area on the inside.
The measured length of the PCBA module is 69.34mm.
The width is 54.09mm.
The thickness is 22.48mm.
On one side of the PCB, there are devices such as a delay fuse, a safety X capacitor, and a high-voltage filter electrolytic capacitor.
The time-delay fuse specification is 3.15A 250V.
Close-up of NTC surge suppression resistor for suppressing upsurge current.
Common-mode inductors are double-wirewound for EMI filtering.
Close-up of safety X capacitor, 0.33μF capacitance.
The rectifier bridge at the input end WRMSB40M is from Shenzhen World Industrial Co., Ltd., and the specification is 4A 1000V. WRMSB40M this flexible bridge has a soft recovery curve and relatively smooth turn-off characteristics, it can reduce the junction capacitance of the diode to achieve the effect of very few harmonic oscillations.
Wald WRMSB40M Profile Information.
The charging head network learned that the World soft bridge has also been used by OPPO 50W biscuit gallium nitride fast charging, Hongdashun 65W gallium nitride charger, flying frequency 65W USB PD GALLIUM NITRIDE charger, ROCK 65W gallium nitride charger, McDuoduo 65W gallium nitride charger, McDuoduo 30W 1A1C fast charging charger and other products, and the performance has been unanimously recognized by customers.
The three high-voltage filter electrolytic capacitors are from Emerald, all of which are 400V 22μF.
I-shaped inductor jacket heat shrinkable tube insulation.
The front end of the module also has a transformer, and the other side is equipped with the power supply capacitor and Y capacitor of the main control chip.
The back of the motherboard is equipped with a rectifier bridge, a primary controller for switching power supplies, a primary switch tube, a synchronous rectifier tube and other devices.
The power supply capacitor of the main control chip comes from Huarong Weiye, and the specification is 50V10μF.
The main control chip adopts Nanxin Technology SC3023, which is a high-frequency quasi-resonant flyback controller with a built-in GaN driver, which can be used for direct-drive enhanced GaN switches. The SC3023 has built-in X-capacitive discharge, high-voltage start-up, and adaptive switching frequency foldback for higher efficiency across the entire load range.
The SC3023 achieves high efficiency with valley turn-on in both QR and DCM modes. Operates in low-power mode when no-load, reducing the standby power consumption of the system. The chip has comprehensive built-in protection functions, including power supply under-voltage/over-voltage protection, cycle-by-cycle over-current protection, two-level over-current protection, output over-voltage and output short-circuit protection.
Nanxin Technology SC3023 information.
The primary switch is from Innoscience, model INN700TK240B, is a 700V reinforced GaN switch with a transient withstand voltage of 800V and a conduction resistance of 240mΩ, which meets the requirements of JEDEC standard for industrial applications, has built-in ESD protection, and is available in a TO252 package.
Close-up of transformer.
EL 1018 optocoupler for output voltage feedback.
Close-up of blue Y capacitor.
The synchronous rectifier controller is from Nanxin Technology, model SC3503, which is an adaptive turn-on detection and fast shutdown synchronous rectifier controller, without auxiliary coil power supply, the output voltage can be as low as 0V, the patented adaptive turn-on detection circuit avoids the mis-opening of the synchronous rectifier tube, compatible with a variety of MOS, with ultra-low quiescent current, supports a variety of working modes, supports high-side and low-side synchronous rectification, and the peripheral components are very streamlined.
Nanxin SC3503 data information.
According to the dismantling of the charging head network, the chip has been used in TEGIC mini 30W gallium nitride fast charging, Greenlink mini 30W gallium nitride fast charging, Zhengtuo 65W 2C1A gallium nitride charger, Weiyuan Xinneng 30W 1A1C gallium nitride fast charging, imagery 65W gallium nitride charger, Nubia 30W gallium nitride fast charging and other products, in addition, Nanxin fast charging chip can also be used in chargers, car chargers, mobile power supplies, energy storage power supplies and other products, and has been used by dozens of products such as Anker, Samsung, Zimi, Yubo, etc. The quality has been highly recognized by customers.
同步整流管来自ALLEPIC禾纳半导体，型号AER10061AE，NMOS，耐压100V，导阻4.5mΩ，采用PDFN5060封装。
A glance at the front of the motherboard, with a two-layer small board in the center, supported by a pin header welding.
The small board is removed, and the lower area is equipped with devices such as filtering solid-state capacitors and inductors.
The two synchronous rectifier output filter solid-state capacitors are from Dongjia, and the specifications are both 25V 680μF.
The synchronous buck-boost converter is from Nanxin Technology, model SC8724. It is a synchronous buck-boost converter with integrated four switches. Regardless of whether the output voltage is high, low, or equal to the input voltage, it provides efficient power efficiency and stable voltage regulation. The SC8724 supports input voltages from 2.7V to 22V, an output voltage range of 3V to 22V, and supports output currents up to 3.5A.
The SC8724 is controlled in average current mode. The output voltage is regulated by a resistor on the FB pin. Both the chip operating mode (PSM/FPWM) and the switching frequency can be adjusted via external settings. The chip also provides a programmable output current limit for flexible support for different applications.
The SC8724 supports internal current limiting, input under-voltage protection, output over-voltage protection, output short-circuit protection, FB short-circuit protection, and over-temperature protection to ensure safety under different abnormal conditions. The SC8724 is available in a 25pin 4x4 QFN package.
Synchronous buck-boost inductor jacket insulating tube.
Close-up of filter inductor.
The secondary filter solid-state capacitor is also from Dongjia, with a specification of 16V 220μF.
Another close-up, with the same specifications.
In addition to soldering 2C1A three USB sockets, the output board is also equipped with a protocol chip and a VBUS switch tube.
There are no soldered devices on the back of the small board.
The USB-C2 port protocol chip adopts the SC2151A of Nanxin Technology, which has obtained USB-IF PD3.0 certification, TID: 4869. Packaged in a 16-pin QFN 4*4mm package, it is a controller that supports PD and DP/DM fast charging protocols, with an integrated feedback loop, supports the latest Type-C and PD3.0 standards, and also supports proprietary fast charging protocols using DP/DM interfaces, making it suitable for various adapter applications.
Nanxin Technology SC2151A integrates a 32-bit high-performance MCU core, integrated 24kB single programming memory and 2kB RAM. The controller integrates USB PD physical layer, Type-C detection, DP/DM fast charging protocol physical layer for various fast charging protocols, and VCONN power supply.
In addition, the fast charging adapter solution has a built-in output discharge path, built-in programmable feedback compensation, voltage and current detection, 10-bit high-performance ADC, two 10-bit DACs, NMOS path tube driver, I2C communication interface, and rich protection circuits, providing a simple and efficient protocol controller solution for adapters and other applications.
Charging head network learned that Nanxin's SC2151A protocol chip has also been used in dozens of products of well-known brands such as Greenlink 30W PD fast-charging gallium nitride charger, Gushi Technology 30W PD fast-charging gallium nitride charger, Anker 30W mini gallium nitride fast charger, Nubia 30W gallium nitride fast charging charger, etc., and the product quality has been unanimously recognized by customers.
The VBUS switch for the USB-C2 interface is from ALLEPIC Hena, model AET3061AP, NMOS, withstand voltage 30V, conduction resistance 6mΩ, and is available in a PDFN3030 package.
USB-C1和USB-A口协议芯片采用富满微XPD702。
Close-up of USB-C2 port receptacle.
Close-up of USB-C1 port receptacle.
Close-up of the USB-A port receptacle.
A list of all dismantling and a family photo.
Summary of the dismantling of the charging head network
Finally, a list of core components of Xiaomi's 67W gallium nitride fast charging plug-in board is attached for your convenience.
The Xiaomi 67W GaN fast charging plug-in board has a simple design style, equipped with three sets of two-pin jacks, three sets of 3+2 new national standard jacks and 2C1A USB interface, which can supply power to up to 9 devices at the same time, meeting the needs of living rooms, bedrooms, desks and other scenarios, and one desktop power is enough. The USB-C port supports up to 67W PD fast charging, and also supports 20W+45W output strategy to meet the needs of laptops and mobile phones.
Through dismantling, the charging head network learned that the AC part inside the plug-in board adopts an integrated copper strip design, which makes the high-quality copper material conduct fast, good heat dissipation, and safer for long-term use under high load. In the fast charging module, Nanxin Technology SC3023+SC3503 high-frequency QR power supply solution is used, and SC8724 is used for secondary voltage reduction, and the USB-C2 port also uses Nanxin Technology's SC2151A protocol chip to control the output. The other two interfaces use the Fuman Micro XPD702 protocol chip to control the output. Emerald and Dongjia capacitors are used for filtering, and the overall materials are reliable.