Nubia RedMagic DAO 140W Quad-port GaN Gan6 Pro Charger Teardown

Nubia’s DAO series has launched a new heavyweight product—the RedMagic DAO 140W Quad-port GaN Gan6 Pro Charger. It not only supports up to 140W PD3.1 fast charging, meeting the full-speed charging needs of the Apple MacBook Pro, but also supports the latest generation of UFCS (Universal Fast Charging Specification) fusion fast charging. Additionally, it is compatible with mainstream fast charging protocols like QC, SCP, and PPS, with excellent overall performance and compatibility.

Moreover, the charger is equipped with four USB ports (3C1A), and the number of ports, along with a variety of output strategies, can meet the charging needs of the entire Apple ecosystem. With this charger, you only need to carry one device when you’re on the go. Below, ChargerLab brings a teardown of the Nubia 140W GaN charger to take a closer look at its internal design and architecture.

The packaging box continues the series' consistent design, with a sleek silver-tone appearance. The top surface is printed with the product's name in both Chinese and English, the DAO logo, and the word "CHARGER."

On the back, there is a product information sticker. The sticker displays the product name, model, manufacturer’s address, and customer service hotline. Inside the packaging, you’ll find the charger, a data cable, and a user manual. The included data cable is neatly bundled with a rubber band. The cable is a USB-C to USB-C type, in classic white, with reinforced ends to resist bending. The actual length of the data cable is approximately 121 cm. Testing with the ChargerLAB POWER-Z KM003C revealed that the cable contains an E-Marker chip, with a power transmission capability of 50V5A and a data transfer capability of USB 2.0.

The charger continues the iconic design of the Nubia Duofeng fast charging family, featuring a silver-gray body with a transparent mechanical style shell at the end. The aesthetics are both striking and impressively hardcore.

Nubia RedMagic DAO 140W Quad-port GaN Gan6 Pro Charger Teardown

The outer casing of the charger's input end was opened, revealing an ultrasonic welding encapsulation. The pins are connected to the PCBA module via wires to supply power.

The PCBA module was extracted, and the pins are secured with screws.

The actual measured length of the PCBA module is 82.3mm.

The width is 53.69mm.

The thickness is 25.83mm.

The PCBA module is covered with Mylar sheets and heat sinks, with the edges of the heat sinks taped with insulating tape.

After removing the heat sinks, the inside of the Mylar sheets reveals black thermal pads to aid in heat dissipation.

A full view of the front side of the PCB shows a black thermal pad on the transformer, and a Mylar sheet providing insulation between the transformer and the small output board. The gaps between components like capacitors and inductors are filled with white glue for reinforcement.

After cleaning off the white glue, the center of the mainboard reveals the transformer, main control chip power supply capacitor, filter capacitors, solid capacitors, and other components.

The backside of the mainboard features the PFC boost controller, PFC boost switch, main control chip, optocoupler, SMD Y capacitors, synchronous rectifier controller, and synchronous rectifier MOSFET, among other components.

A front view of the PCBA module shows the fuse, NTC thermistor, safety X capacitors, common-mode inductors, and a small rectifier bridge board, with two rectifier bridges on the back of the small board.

After removing the small board, the other side reveals two additional safety X capacitors, common-mode inductors, filter capacitors, and filter inductors.

The fuse is protected by a heat-shrink tube.

The NTC thermistor is also protected by a heat-shrink tube.

A close-up of the green NTC thermistor, used to suppress inrush current during power-on.

The safety X capacitor is from JURCC Jiewei, with a capacitance of 0.68μF.

The common-mode inductor is wound with two wires to filter out EMI interference.

The two additional safety X capacitors are also from Jiewei Electronics, with a capacitance of 0.22μF.

A close-up of the other common-mode inductor, featuring a two-stage design.

The two rectifier bridges are from PY Pingwei, model TBM810, with a specification of 8A1000V, using TBM packaging.

A close-up of the filter inductor.

The CBB22 film capacitor has a specification of 1μF450V.

Another close-up of a film capacitor with a specification of 0.47μF 450V.

One end of the mainboard features the PFC boost inductor and high-voltage filter electrolytic capacitor, with the capacitor protected by a sleeve.

The other end reveals the secondary buck inductor for the USB-C1 port and other components.

The PFC boost controller has the marking 3CCRTH, which is actually ON Semiconductor's NCP1622, an enhanced critical conduction mode boost PFC controller with valley frequency foldback, improved transient response, and efficiency, and simplified external components. The NCP1622 corrects the power factor of the pulsating DC output from the rectifier bridge to supply the switching power supply.

The PFC boost switch is from InnoScience, model INN650D150A, a 650V GaN high-voltage single transistor with a transient voltage of 750V, a resistance of 150mΩ, and DFN8*8 packaging. The INN650D150A supports ultra-high switching frequency, has no reverse recovery charge, features very low gate charge and output charge, complies with JEDEC standards for industrial applications, includes built-in ESD protection, and meets RoHS, lead-free, and EU REACH regulations.

A close-up of the PFC boost inductor.

The PFC boost rectifier diode is from PANJIT, model MURC5J, a 5A, 600V ultra-fast recovery diode.

The diode marked GN6M is a PFC bypass diode, rated for 1000V and 6A, used to charge the filter capacitor when the power is connected.

The high-voltage filter electrolytic capacitor is from YMIN, with a capacitance of 450V 100μF.

A close-up of the CBB21 series filter capacitor, with a specification of 0.47μF 630V.

Two main control chip power supply capacitors are from BERYL, with a specification of 50V 10μF.

The main control chip is the Dongke Semiconductor DK8715AD, a power switch chip based on an asymmetrical half-bridge architecture that integrates two GaN power devices for AC-DC conversion. It can achieve ZVS for the primary power switch and ZCS for the secondary rectifier over a wide load range, improving power system efficiency. The soft-switching also reduces stress on the power switch, and the built-in full-range frequency jitter circuit reduces switching losses and improves electromagnetic interference.

The DK8715AD has a simplified external circuit, which greatly simplifies the design and manufacturing of AC-DC converters, especially for products requiring high conversion efficiency and power density. The DK8715AD offers comprehensive protection functions, including overload protection, output overvoltage protection, output short-circuit protection, VCC over/undervoltage protection, VS pin abnormal protection, primary overcurrent protection, and over-temperature protection.

The DK8715AD supports a maximum switching frequency of 800KHz. With a front-end boost PFC, the recommended power is 150W (for high power density and small size applications), standby power consumption is less than 50mW, and it features an adaptive dead-time and shutdown algorithm with no need for external adjustment. The external circuit is extremely simplified, and it is halogen-free, RoHS compliant, with built-in high-voltage start-up and X capacitor discharge circuits for higher system performance and reliability. The DK8715AD adapts to four load modes to effectively improve efficiency across all load segments, achieving up to 95.4% efficiency when used in a device.

DK8715AD Typical Application Diagram

The DK8715AD integrates two 650V enhanced GaN HEMTs with a half-bridge drive and AHB control. It has a built-in half-bridge drive circuit and asymmetric half-bridge control circuit. The upper transistor features an adaptive shutdown technology for automatic shutdown when needed, while the lower transistor uses adaptive dead-time technology to effectively prevent dead-time effects. It also comes with multifunctional pins for demagnetization detection, output OVP, Brown in/out, and other functions, as well as CS negative sampling to enhance drive stability.

The DK8715AD is packaged in DFN8*8 and is suitable for high power density fast chargers, adapters, notebook adapters, tablet adapters, TV power supplies, two-wheeler chargers, communication power supplies, LED power supplies, and other fields.

A close-up of the transformer.

TD 1019 optocoupler, used for output voltage feedback.

The surface-mount Y capacitor is from Sichuan Teryx Technology Co., Ltd., featuring a small size and lightweight design, making it highly suitable for high-density power products like GaN fast chargers. The part number is TMY1681M.

Teryx focuses on the research, development, production, and sales of passive components, with a registered capital of 100 million RMB. It owns two self-developed capacitor brands: SMD TRX and DIP TY capacitors. TRX is dedicated to the research of ceramic materials to expand the application of more categories, providing more solutions to customers.

It has been learned that Teryx's surface-mount Y capacitors are not only used in high-power chargers like MCDODO 100W GaN, OPPO 65W SuperVOOC GaN charger, Lenovo 90W GaN fast charger, and dozens of others, but can also be applied in 20W mini fast chargers from brands like Huntkey, First Guard, and Belkin, with performance unanimously recognized by customers.

Another close-up of Teryx's surface-mount Y capacitor, part number TMY1221K.

The synchronous rectifier controller with silk-screen marking IBHJP is actually the MP6908A from MPS Semiconductors, with a maximum operating frequency of 600KHz. It supports various operation modes like DCM, CCM, QR, and ACF, and is compatible with both high-side and low-side applications, featuring ring detection to prevent false turn-on.

Close-up of two synchronous rectifier MOSFETs, from Nuvoton, with silk-screen marking XTMT12N110L.

The high-voltage filtering electrolytic capacitor is from BERYL, with specifications of 35V 680μF.

Another one is also from BERYL, with specifications of 35V 470μF.

Close-up of the filtering inductor.

Overview of the output end, with a small vertically soldered board on the left, housing four USB female sockets (3C1A) on the small board.

Upon removing the small board, the front side features the USB-C2 port buck controller, buck inductor, and two sets of solid-state filtering capacitors.

The backside houses the USB-C1, USB-C3, and USB-A buck controllers, buck inductors, synchronous buck MOSFETs, and output VBUS switch MOSFETs.

The USB-C1 port of the charger uses the ISW SW3566H buck controller, a highly integrated dual-port charging SoC chip supporting USB-C and USB-A interfaces. It also supports dual-port independent current limiting. The chip integrates a high-efficiency synchronous buck converter, supports 20V7A and 28V5A output, and is compatible with fast charging protocols like PD3.1/QC/SCP/UFCS, with support for fast charge protocol customization, and a maximum output power of 140W.

The SW3566H integrates CC/CV mode, dual-port management logic, and bus voltage detection. With the corresponding buck MOSFET and VBUS switch MOSFET, it can achieve dual-port buck output. The built-in buck converter operates at a frequency of 180KHz and supports PWM and PFM operating modes. The output current, line loss compensation, and other protection thresholds can be set via the I2C interface. The built-in ADC supports data sampling from 9 channels, including input/output voltage, output current, and chip temperature, with external MCU parameter display support.

The SW3566H supports a 36V input voltage, with a maximum output current of 7A. The chip includes soft-start, input over-voltage/under-voltage protection, output over-voltage/under-voltage protection, output over-current/short-circuit protection, DP/DM/CC over-voltage protection, chip over-temperature protection, and external NTC thermistor protection, as well as power limit protection. The chip is packaged in a QFN4*4-32 package.

The ISW SW3566H has also been adopted in products like the Anker 65W 2C1A GaN charger, Bull 240W 3C1A GaN desktop charger, UGREEN 300W 4C1A five-port PD GaN fast charger, INKOMAX 140W 3C1A GaN fast charger, GUSTONE 188W multi-port desktop charger, and TOMAX 140W 3C1A GaN charger, with the chip’s performance and quality receiving unanimous recognition from customers.

The synchronous buck MOSFET is from AGMSEMi Core, model AGM405AP1, a 40V NMOS with an on-resistance of 5.7mΩ, packaged in DFN3.3*3.3.

Another one is on the other side of the mainboard, also AGMSEMi Core AGM405AP1.

Close-up of the buck inductor.

Two filtering solid-state capacitors from KOSHIN, with specifications of 35V 220μF, used for the secondary buck output filtering of the USB-C1 port.

The USB-C1 port output VBUS switch MOSFET also uses the AGMSEMi Core AGM405AP1.

The USB-C2 port buck output uses the ISW SW3556 chip, which supports dual USB-C interface buck control, integrates various fast charging protocols, supports 7A high current output, and supports dual-port power blind insertion and independent current limiting. The SW3556 supports driving low-voltage GaN MOSFETs, further improving the efficiency of the buck circuit, reducing the size and heat dissipation requirements of the charger.

The ISW SW3556 uses a synchronous rectification buck topology, supports 40V input, and integrates a synchronous rectification buck controller. With the use of silicon MOSFETs or GaN MOSFETs, inductors, capacitors, and other simple external components, it can achieve 140W high-power output. The built-in buck controller operates at a frequency of 125KHz, supporting PFM/PWM mode operation to optimize conversion efficiency.

Additionally, the ISW SW3556 supports pin-configurable output power and dynamic power distribution using external resistors, eliminating the need for an external MCU when developing multi-port fast-charging power products, thus achieving more streamlined peripherals and reducing costs. It is suitable for car chargers, multi-port chargers, power strips, and other product areas.

The USB-C2 port secondary buck circuit's synchronous buck MOSFET also uses the AGMSEMi Core AGM405AP1.

Another AGMSEMi Core AGM405AP1 is on the backside of the small output board.

Another buck inductor is sleeved with an insulating tube.

Two filtering solid-state capacitors from BERYL, with specifications of 25V 220μF.

The USB-C2 port output VBUS switch MOSFET also uses the AGMSEMi Core AGM405AP1.

The buck chip for the USB-C3 and USB-A ports is the ISW SW3537, which integrates a 5A high-efficiency synchronous rectification buck converter, supports PPS, PD, QC, AFC, FCP, SCP, PE, SFCP, low-voltage direct charging, and other charging protocols, supports CC/CV mode, and requires only a few external components to form a complete high-performance multi-fast charge protocol dual-port charging solution.

Thanks to its high integration, the SW3537 integrates the protocol chip, synchronous buck controller, and buck MOSFET of the traditional buck solution into one package, greatly simplifying the circuit design of multi-port fast charging. The chip supports A+C dual-port fast charging applications and has comprehensive protection functions.

Close-up of the 4R7 buck inductor.

Two other filtering solid-state capacitors from YMIN, with specifications of 35V 180μF.

The USB-C3 port and USB-A port output VBUS switch MOSFETs both use the RUICHIPS RU3040, an NMOS with a 30V voltage rating.

Close-up of another RUICHIPS RU3040.

Close-up of the three USB-C female sockets.

Close-up of the USB-A female socket.

A complete teardown overview, with a family photo.

The Nubia RedMagic DAO 140W Quad-port GaN Gan6 Pro Charger continues the family series design, with a transparent top cover showing internal components, giving it a very hardcore appearance. The new product is equipped with four USB ports (3C1A), supporting 140W, 100W, 30W, and 27W outputs, respectively, and supports output strategies like 65W+30W+20W, 65W+20W+12W+12W, meeting the simultaneous fast charging needs of Apple MacBook, iPad, iPhone, Apple Watch, and AirPods devices. It is the most powerful new product in the Duofeng series, worth considering.

From the teardown, it is learned that this charger is designed based on the PFC+AHB power architecture, with the PFC circuit using the ON Semiconductor NCP1622 controller paired with the Innoscience INN650D150A GaN power device. The switching power supply uses the Dongke Semiconductor DK8715AD paired with MPS MP6908A, and the four-port output uses three buck protocol chips: ISW SW3566H, SW3556, and SW3537.

The filtering capacitors are from BERYL, YMIN, and KOSHIN. After soldering the components on the PCB board, white glue is filled in for reinforcement, ensuring long-term stable operation. The module is covered with a large heat sink, with the back of the mainboard and the transformer additionally equipped with thermal pads for better heat dissipation. The workmanship and materials are solid and reliable.