Introduction
HuntKey has launched a 45W GaN charger featuring an integrated retractable USB-C cable and a USB-C port. Both the cable and the port support up to 45W output and are compatible with multiple protocols, including PD 3.0 and PPS. When both ports are used simultaneously, the power can be distributed at 22.5W + 22.5W. The following teardown examines its internal structure and components to assess build quality and material selection.
Product Appearance
The enclosure features a two-tone gray-and-black design with smoothly rounded edges and corners.
The front surface is marked with "45W GaN."
The top center is printed with "HuntKey."
This side is equipped with the USB-C1 retractable cable and the USB-C2 port.
The cable connector features a metal housing and is marked with "C1" on the front.
The housing includes a slot for retracting and storing the cable.
Below the USB-C2 port, “C2” and “DESIGN BY HUNTKEY” are printed.
The bottom of the housing is printed with the specifications.
Model: HKC04520023-0J2
Input: 100-240V~ 50/60Hz 1.5A
Output:
C1/C2: 5V 3A, 9V 3A, 12V 3A, 15V 3A, 20V 2.25A, Max 45W
Dual-Port Output:
C1 + C2: 5V 2A, 9V 2A, 12V 1.875A (22.5W Max + 22.5W Max)
The product is ETL certified and meets Level VI energy efficiency standards.
It is equipped with foldable pins.
The length of the charger is about 61.78 mm (2.43 inches).
The width is about 58.93 mm (2.32 inches).
The thickness is about 36.87 mm (1.45 inches).
The length of the cable is about 72 cm (28.35 inches).
That's how big it is in the hand.
The weight is about 128 g (4.52 oz).
ChargerLAB POWER-Z KM003C shows that the USB-C cable supports QC3.0/5, FCP, SCP, AFC, PD3.0, PPS, DCP, and Apple 2.4A charging protocols.
It features five fixed PDOs: 5V 3A, 9V 3A, 12V 3A, 15V 3A, 20V 2.25A, as well as two PPS voltage ranges: 5–11V 5A and 5–21V 3.25A.
The USB-C port is compatible with the same protocols as the USB-C cable.
The PDO messages are identical as well.
Teardown
Next, let's take it apart to see its internal components and structure.
Cut along the seam to open the case. The PCBA module and the retractable cable module are each fixed to separate halves of the housing, connected by wires.
The back of the PCBA module is covered with a Mylar sheet and a metal heat sink.
The PCBA module is connected to the plug pins via wires. The housing includes an integrated plastic barrier for primary-to-secondary isolation.
The components on the front of the PCBA module, such as capacitors and the transformer, are reinforced with adhesive.
The length of the PCBA module is about 54.18 mm (2.13 inches).
The width is about 55.61 mm (2.19 inches).
The thickness is about 18.67 mm (0.74 inches).
The front of the PCBA module contains a fuse, common mode choke, capacitors, a transformer, switching MOSFETs, and a VBUS MOSFET.
The back of the PCBA module houses a bridge rectifier, master control chip, synchronous rectifier, protocol chip, and VBUS MOSFET.
The delay fuse is from Betterfuse, part number 932, rated at 3.15A 250V~.
The NTC thermistor is used to suppress inrush current at power-on.
The common mode choke is used to filter EMI interference and is insulated with a heat-shrink sleeve.
The bridge rectifier is from PY, model TMBFR310, rated at 3A 1000V, and comes in a TMBF package.
The two high-voltage filter electrolytic capacitors are from AiSHi.
The brown capacitor is rated at 400V 15μF.
The black capacitor is rated at 400V 12μF.
The I-shaped inductor is insulated with a heat-shrink sleeve.
The third high-voltage filter electrolytic capacitor is from SAMXON, rated at 400V 33μF.
The capacitor supplying power to the master control chip is rated at 50V 22μF.
The master control chip is from SouthChip, model SC3107M. It uses SouthChip’s fully integrated high-voltage isolated package, incorporating the primary controller, high-voltage GaN power transistor, high-speed isolated communication, secondary synchronous rectification controller, and high-frequency switching path MOS driver.
The high integration level of the SC3107M significantly reduces the number of peripheral components in the charger. It can replace multiple discrete chips in conventional power solutions, enabling a more compact power design while offering advantages such as shorter development cycles and higher cost-effectiveness.
The SC3107M integrates a high-speed digital isolation communication module, SC-PQLINK®, which not only offers higher system reliability than optocouplers but also enables precise control on the secondary side.
Leveraging secondary-side control, it achieves primary-side ZVS and active synchronous rectification, significantly improving overall power efficiency and reducing thermal requirements. The chip’s dual-output channels can be independently regulated; through high-frequency switching technology, it ensures stable adjustment and natural commutation of both outputs without the need for additional DC-DC converters, effectively eliminating voltage spikes.
The SC3107M also integrates advanced functions such as soft start, intelligent frequency jitter, smart power path control, and lossless current sensing. It includes comprehensive protection mechanisms: PVCC overvoltage/undervoltage protection, SVCC undervoltage protection, VIN overvoltage protection, cycle-by-cycle current limit, output overvoltage protection, output short-circuit protection, overload protection, and over-temperature protection. Housed in an SSOP38L package, it is well-suited for high-performance, multi-output fast-charging power designs.
The transformer is reinforced with a plastic casing for insulation.
Close-up of the blue Y-capacitor.
The synchronous rectifier is from PY, model PW055N10ESL, an N-channel MOSFET with a voltage rating of 100V and an on-resistance of 4.4 mΩ, packaged in a DFN 5×6.
All four switching MOSFETs are marked Q35N03A and use a PDFN3333-8L package.
All four solid capacitors are from the SAMXON ULR series, each rated at 25V 330μF.
The protocol chip is from SouthChip, model SC2167B. It is a fast-charging controller that supports dual C-Source ports and all mainstream fast-charging protocols, featuring CC and DPDM interfaces. Its target applications include multi-port chargers, car chargers, and similar devices.
The SC2167B integrates fast-charging protocol circuits, including Type-C/PD circuitry, DPDM/UFCS circuitry, VBUS discharge paths, voltage and current sensing, an 11-bit high-performance ADC, two 11-bit DACs, NMOS gate drivers, an I²C interface, and protection circuits, minimizing the need for external components. It also features a built-in 32-bit high-performance microcontroller with 64KB Flash and 8KB SRAM, providing a cost-effective solution for a wide range of applications.
The SC2167B supports multiple protection mechanisms, including overvoltage protection, undervoltage protection, overcurrent protection, short-circuit protection, overtemperature protection, DPDM overvoltage protection, CC overvoltage protection, and VCONN overvoltage, overcurrent, and short-circuit protection, effectively ensuring stable and reliable system operation.
The output VBUS MOSFET is also marked Q35N03A.
The other VBUS MOSFET has the same part number.
The retractable cable module is mounted on the other half of the housing and secured with clips.
Overview of the retractable cable module after disassembly.
Close-up of the PCB slip ring.
The spool is equipped with three brushes to increase current-carrying capacity.
Well, those are all components of the HuntKey 45W GaN Charger.
Summary of ChargerLAB
Here is the component list of the HuntKey 45W GaN Charger for your convenience.
It features a two-tone gray and black design and comes with foldable plug pins, making it compact and easy to carry. The integrated retractable USB-C charging cable combines portability with practicality.
After taking it apart, we found that it uses the highly integrated SouthChip master control chip SC3107M, which significantly reduces the number of peripheral components and enables primary-side zero-voltage switching and active synchronous rectification, markedly improving overall power efficiency and reducing thermal requirements.
Paired with the HuntKey SC2167B protocol chip, it enables control of both the retractable cable and the port outputs, as well as intelligent power distribution. Key component areas are reinforced with adhesive and covered with metal heat sinks and Mylar sheets for improved thermal management, demonstrating careful material selection and workmanship.
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