preface
Recently, ROMOSS launched a new 65W fast charging charger AC65MC, this new product not only has 2C1A mainstream interface and folding pin configuration, but also has a new generation of UFCS fusion fast charging blessing, plus it also supports QC3.0/5, PD3.0, PPS and other fast charging, the overall compatibility will be very good.
In addition, the product also uses gallium nitride technology, plus the internal use of Mini structure stacking technology, the overall body is small and portable. The shell is treated with innovative thin rhyme floating light technology, and the appearance is also good. The following charging head network will disassemble it in detail, let's take a look.
Romax 65W GaN charger unboxing
The front of the box is printed with the ROMOSS brand, the appearance and name of the product set, as well as the four selling points of multi-port fast charging, intelligent adaptation, ten-fold protection, and folding pins.
The back is printed with charger parameters and business information.
Close-up of the parameters on the packaging box, and then introduce it to the physical display of the product.
The package contains a charger, a data cable, and an instruction manual.
The length of the measured data cable is about 145cm.
使用ChargerLAB POWER-Z KM003C测得线缆带有E-Marker芯片，电力传输能力为50V5A，数据传输能力为USB 2.0。
The charger is made of PC fireproof plastic shell, the overall surface of the fuselage is matte processed, and the touch does not stick to fingerprints, and the corners are designed to be rounded.
腰身一面印有ROMOSS品牌和65W GaN。
The input housing is printed with charger parameter information.
Close-up of charger parameters
Model: AC65MC
输入：100-240V~50/60Hz 1.5A Max
Output:
USB-C1/C2:5V3A、9V3A、12V3A、15V3A、20V3.25A 65W Max
PPS:3.3-11V4.08A、3.3-21V3A
UFCS：5.5-11V4A 44W Max
USB-A:5V3A、9V3A、12V2.5A 30W Max
USB-C1+USB-C2：45W+20W
USB-C1+USB-A：45W+18W
USB-C+USB-C2+USB-A：45W+15W
USB-C2+USB-A：5V3A
Manufacturer: Jiangmen Roma Technology Co., Ltd
Entrusting party: Shenzhen Roma Technology Co., Ltd
The charger is CCC certified, as well as Class VI energy efficiency certified.
The charger is equipped with foldable GB prongs for easy portability.
The other end is equipped with 2C1A three USB interfaces, the interface cores are purple, and the 65W and 30W logos are printed on the side, so that users can intuitively understand the output parameters of the charger.
The measured length of the charger body is 67.22mm.
The width is 32.91mm.
The thickness is 38mm.
Compared with Apple's 61W charger, the size advantage is obvious.
Feel the size of the charger in your hand.
In addition, the net weight of the charger is measured to be about 133g.
使用KM003C测得USB-C1口支持UFCS、FCP、SCP、AFC、TFCP、QC3.0/5、PD3.0、PPS、DCP、SAM 2A、Apple 2.4A充电协议。
PDO报文显示USB-C1口还具备5V3A、9V3A、12V3A、15V3A、20V3.25A五组固定电压档位,以及3.3-11V4.05A、3.3-21V3A两组PPS电压档位。
In addition, it is measured that UFCS fast charging supports a set of voltage levels of 5.5-11V4A.
测得USB-C2口同样支持UFCS、FCP、SCP、AFC、TFCP、QC3.0/5、PD3.0、PPS、DCP、SAM 2A、Apple 2.4A充电协议。
PDO报文显示USB-C2口也具备5V3A、9V3A、12V3A、15V3A、20V3.25A五组固定电压档位,以及3.3-11V4.05A、3.3-21V3A两组PPS电压档位。
It is measured that UFCS fast charging supports a set of voltage levels of 5.5-11V3A.
最后测得USB-A口支持UFCS、QC3.0、FCP、SCP、AFC、DCP、SAM 2A充电协议。
It is measured that UFCS fast charging supports a set of voltage levels of 5.5-11V3A.
Romax 65W GaN charger disassembled
After reading the appearance and protocol test of this charger of Romas, let's disassemble it and take a look at the internal design and materials.
The charger input shell is disassembled, the internal PCBA module is glued and treated, and the pin and PCB board are energized through shrapnel contact.
The PCBA module is very firmly fixed, and the main body shell can only be cut and taken out.
The measured module length is 54.86mm.
The width is 33.01mm.
The thickness is 27.64mm.
The top and both sides of the module are covered with U-shaped brass heat sinks, while the inner side is insulated with Mylar sheets.
The back of the motherboard also features brass heatsinks and Mylar tabs.
Remove the heatsink on the back of the motherboard, and glue the corresponding core device area to help conduct heat.
The front heat sink is also removed, and the front of the module is glued into a whole to improve the overall weather resistance and heat dissipation performance.
The white glue is cleaned off, and the front device of the board is a classic three-stage layout, and the input and output terminals are designed with independent small boards.
The back of the motherboard is equipped with a switching power supply main control chip, a synchronous rectifier controller, a chip Y capacitor, an optocoupler, etc.
The input terminals of the module are listed at a glance, and the motherboard is equipped with a delay fuse, I-shaped inductor and high-voltage filter electrolytic capacitor, and the side board is equipped with NTC surge suppression resistor and safety X capacitor.
The small plate is removed, and the front of the board is also equipped with a common mode inductor and a rectifier bridge.
Close-up of the delay fuse, the 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.
The safety X capacitor capacity is 0.22μF.
The rectifier bridge is from Shenzhen World Industrial Co., Ltd., model WRLSB80M, this soft bridge can reduce the diode junction capacitance to achieve very little harmonic oscillation through a softer recovery curve and relatively smooth shutdown characteristics. The selected LSB package has good heat dissipation characteristics, which helps the medium and large wattage adapter improve reliability, and a single adapter can be 60W+.
Wald WRLSB80M Profile Information.
According to the dismantling of the charging head network, Wald's soft bridge has also been used in a variety of fast charging products such as Momis 100W 2A2C gallium nitride fast charging, Nubia 1A1C 45W deuterium front gallium nitride fast charger, Bull 65W PD fast charging socket, Maiduoduo 2C1A 65W gallium nitride charger, Hongdashun 65W gallium nitride charger, OPPO 50W biscuit gallium nitride fast charging, ROCK 65W gallium nitride charger and other fast charging products, and the product performance has been unanimously recognized by customers.
I-shaped inductor jacket insulating tube.
The three black high-voltage filter electrolytic capacitors are of the same brand, and the specifications are all 400V 27μF.
The fourth one adopts Yongming KCX series, with a specification of 400V and 33μF.
There is a transformer in the middle area of the motherboard.
On the other side of the transformer, there is a synchronous rectifier tube and an output filtering solid capacitor.
The main control chip of the switching power supply adopts Zhirong SW1125 encapsulated gallium nitride chip, which is a high-frequency quasi-resonant flyback converter with integrated 650V withstand voltage and 260mΩ conductive resistance gallium nitride switch tube, and the chip integrates a 700V high-voltage start-up circuit, line voltage power-down detection and X-capacitor discharge function.
The SW1125 operates in valley-open mode with valley lockout to reduce switching losses and integrate frequency jitter to optimize EMI performance. The chip supports burst mode, which automatically enters burst mode when the load is reduced to optimize the light-load efficiency, and the no-load standby power consumption is less than 50mW, which meets the six-level energy consumption requirements.
The SW1125 supports 8-90V ultra-wide range power supply, supports up to 300KHz switching frequency, and adopts a thermally enhanced QFN6*8 package, which can reduce the temperature rise of the chip through via thermal conductivity, optimize the wiring, and simplify the heat dissipation design. The chip has multiple built-in protection functions, and supports external NTC to detect the temperature rise of the charger to achieve a comprehensive protection design.
Close-up of transformer.
贴片Y电容来自STE松田电子,型号STESMDY5U152M。
Everlight EL 1019 optocoupler for output voltage feedback.
The synchronous rectifier controller adopts Zhirong SW1608, which is a high-performance controller driven by a secondary-side synchronous rectifier (MOSFET) for offline flyback converters, in a SOT23-6 package, which supports 6V or 9V VCC power supply, and VCC has a self-power function, no auxiliary winding power supply and supports a wide output voltage range, and the use of MOSFETs instead of Schottky rectifier diodes can significantly improve system efficiency.
SW1608 supports 600KHz working frequency, and supports multiple application scenarios of High Side/Low Side, and supports multiple working modes of CCM/QR/DCM. In addition, it has an integrated intelligent conduction detection function, which can effectively prevent misleading turn-on caused by DCM ringing; The chip also has ultra-low turn-off transmission delay time and strong pull-down current capability, which can significantly reduce the voltage stress of the rectifier tube.
According to the dismantling of the charging head network, Zhirong Technology's SW1125/SW1106+SW1608 gallium nitride power supply scheme has also been used by Yajingyuan 65W 2C1A gallium nitride charger, Xiwei 100W 3C1A ultra-cost-effective gallium nitride fast charging, Juhai 65W 2C1A gallium nitride charger, Hongdashun 65W triple USB-C port gallium nitride charger and other products.
The synchronous rectifier tube is from PY Pingwei, model PW055N10ESL, NMOS, withstand voltage 100V, conduction resistance 4.4mΩ, and DFN5*6 package.
The output filtered solid-state capacitor specification is 25V 680μF.
The three USB receptacles at the output end are all soldered with independent small plates.
Remove the small plates.
The USB-C1 receptacle is equipped with a step-down inductor and a secondary filter solid-state capacitor on the front of the board.
The back of the small board is equipped with a step-down protocol chip, a step-down switch and an output VBUS switch.
The USB-C1 port step-down protocol IC adopts Zhirong SW3561, which is a step-down SoC chip that supports dual USB-C port outputs, with an integrated high-efficiency synchronous step-down controller inside the chip, supports 20V5A power output, and supports USB PD3.1 SPR. The chip integrates ARM Cortex-M0 core, integrates Type-C logic, supports PD3.1/QC/SCP/UFCS fusion fast charging and other fast charging protocols, supports fast charging protocol customization, and supports 100W power output.
Zhirong SW3561 has an integrated step-down converter, dual USB-C port channel control, bus voltage detection, and two synchronous step-down switches and VBUS switches to achieve dual-port step-down output. The default working frequency of the buck converter is 180KHz, which supports customized working frequency to meet the small size design.
According to the dismantling of the charging head network, Zhirong Technology SW3561 has previously been used by Juhai 100W 2A2C gallium nitride charger.
The two synchronous step-down switches are from Zhirong Technology, with SWT40N45 models and DFN3*3 packages.
Close-up of buck inductor.
The specification of the secondary filter solid-state capacitor is 25V 100μF, which is from Dongjia.
The VBUS switch is from PY Pingwei, model D50N03HL, is a NMOS with a withstand voltage of 30V and a conduction resistance of 2.9mΩ, and is packaged in DFN3*3.
The front of the USB-C2 port female board is also equipped with a step-down inductor and a solid-state capacitor.
On the back of the board, there are corresponding devices for USB-C2 and USB-A port output buck circuits.
In addition, the 1A1C dual-port fast charging step-down protocol chip also uses Zhirong SW3561.
The two synchronous step-down switches are also made of intelligent SWT40N45.
Close-up of buck inductor.
The secondary filter solid-state capacitor is also from Dongjia, and the specification is also 25V 100μF.
The output VBUS switch is from Astatine, model AD30N56D3.
Another close-up, of the same model.
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
The Romax 65W GaN charger has a more durable design, and thanks to the use of Zhirong's highly integrated GaN power supply solution, the volume control is also quite good. Another highlight of the product is the configuration of the 2C1A interface, and all of them support a new generation of UFCS fusion fast charging, and the power can reach up to 44W, which can meet the needs of users for a long time in the future without being eliminated.
In addition, the set is also equipped with a USB-C cable that can support PD3.1 240W fast charging, even so, the price of the whole set is only 89 yuan, it will be cheaper to use coupons, it can be said that it is very competitive, and it is worth considering for those who need to start in the near future.
Through dismantling, the charging head network learned that this charger is based on the design of Zhirong SW1125 + SW1608 encapsulated gallium nitride power supply scheme, and the two DC-DC secondary step-down circuits are also designed with Zhirong SW3561H, using electrolytic capacitors and solid-state capacitors for input and output filtering.
At the same time, in terms of structural design, the classic three-stage layout cleverly uses the stacking design of four small PCB boards to minimize the module and further improve the power density. The module is covered with brass heat sink for heat dissipation, and is insulated with Mylar blades.