Introduction
ChargersLAB is checking out a new 65W 2 USB-Cs and USB-A charging solution from SEMITRONIC, featuring two BUCK circuits powered by Meraki and MSI silicon. It’s got a super compact, high-density design and comes loaded with fast-charging protocols and solid thermal protection. Now let’s dive into its overall design and details.
Product Appearance
It features foldable prongs for better portability. For output, it’s rocking two USB-Cs and a USB-A.
Pulling out the PCBA, it uses a dense, stacked 3D structure with multiple boards to maximize every inch of space. On the left, the output board is vertically soldered to the PCB, carrying the 2 USB-Cs and USB-A ports, buck alloy inductors, and three solid caps.
The middle section is packed with high-voltage electrolytic filter caps, while the right edge holds the input filtering and protection daughterboard. Flip it to the back, and the transformer board carries the primary controller, SR (synchronous rectifier) chip, and the transformer itself.
The back view gives us a clear look at the transformer, wrapped in plenty of yellow fire-retardant tape. There's also a handful of Y-capacitors and an optocoupler nearby.
The length of the PCBA is about 48.89 mm (1.920 inches).
The width of the PCBA is about 47.90 mm (1.890 inches).
The thickness of the PCBA is about 21.70 mm (0.850 inches).
The weight is about 45.3g (1.60 oz).
It features two BUCK stages. this solution allows for full 65W output on either C1 or C2 during single-port use, while the USB-A port is rated for 18W.
Here’s how the power breaks down when you’re using multiple ports:
C1+C2：45W+20W.
C1+A：45W+18W.
C2+A：5V3A.
C1+C2+A：45W+5V3A.
Supports 50mV/A Cable Compensation and 120% OCP, plus NTC thermal protection (100°C trigger / 80°C recovery).
It supports QC2.0、QC3.0、Samsung 5V/2A, AFC, FCP, SCP, PD3.0, PPS, AVS and Apple 5V/2.4A, DCP 5V/1.5A.
Breakdown
Input protection: An SQT 3.15A 250V time-delay fuse covers OCP.
On the right, we have a common mode choke for EMI, plus an X2 safety cap sitting at the bottom.
An NTC thermistor.
The rectifier bridge is marked RHBS80M.
On the main PCB, we’ve got a 400V 39μF high-voltage filter cap from CyXincon.
Next to the high-voltage filter cap is a differential-mode inductor wrapped in black heat shrink tubing.
Four more CyXincon 400V 22μF high-voltage caps complete the input filtering.
Two 25V 100μF solid caps and one 25V 330μF cap handle the output side.
A KL1019506 optocoupler handles voltage feedback. Next to it are two TRX TMY1471K SMD Y-caps, chosen for their compact, low-profile design—perfect for high-density GaN chargers.
TRX SMD Y-capacitor info.
A planar transformer is soldered to the side of the PCBA module.
Desoldering the planar transformer reveals the primary controller and synchronous rectification (SR) circuits on the right side of the PCB.
Both the primary controller and the SR chip used in this solution are from Meraki, specifically models MK2706 and MK1206HADE.
The Meraki MK2706 is a QR controller optimized for PD fast charging, integrating a 650V 170mR GaN FET in a DFN6*8 package. It features an ultra-wide VCC range of 9V to 85V, supporting 3.3V to 21V PD/PPS output without the need for extra VCC windings or linear LDO circuits.
The MK2706 operates in DCM or QR modes and switches to Burst mode at light loads to optimize efficiency across all conditions and easily meet energy standards.
Additionally, its compact DFN6x8 package offers comprehensive system-level protection, including output OVP, OPP, VCC OVP, secondary SR short-circuit protection, and CS short-circuit protection for high reliability.
After looking at the primary controller, let’s move on to the integrated synchronous rectification (SR) chip.
The Meraki MK1206HADE is an SR controller designed specifically for high-performance flyback converters. It integrates a controller and a 6.5mΩ 100V power MOS, with full compatibility for CCM, DCM, and QR modes.
This chip is perfect for PD adapters for phones and laptops, high-power density supplies, and battery chargers.
It features self-powering capability, generating its own supply voltage without relying on an auxiliary transformer winding, which adds design flexibility.
Furthermore, its 10ns turn-off propagation delay and ~4A driver sink current effectively improve voltage stress in CCM mode, boosting overall efficiency.
The protocol chip for this solution is from MSI, model CV6659. It is a highly integrated single-chip, three-port protocol controller with dual synchronous buck controllers, designed for feature-rich and stable multi-port charging.
It supports C+C+A or C+A+A configurations and features independent plug and current detection for all three ports.
It supports USB PD3.2 (including SPR, PPS, and AVS) and is compatible with QC5.0, QC4.0+, QC3.0, QC2.0, FCP, SCP, AFC, BC1.2 DCP, and Apple 5V/2.4A to intelligently match any device.
The CV6659 comes in a compact QFN48 package, supports up to 30V, and provides 4000V ESD protection.
The output VBUS switches consist of four MOS tubes: two AGM308AP from AGM Micro and two SWT40N45 from iSmartWare.
Summary of ChargerLAB
This 65W fast charging solution from SEMITRONIC is compact, utilizing a high-frequency transformer with a secondary SR + twoBUCK architecture.
Thanks to the integrated GaN and ultra-wide VCC of the Meraki MK2706, combined with the self-powering and 10ns delay of the MK1206HADE SR chip, it slashes switching losses and simplifies transformer design.
The MSI CV6659 protocol chip enables dynamic power allocation, 65W blind-plugging on USB-C, and multi-port fast charging.
With 50mV/A Cable Compensation, 120% OCP, NTC thermal control, and full protocol support (PD3.0, PPS, AVS), this is a highly polished and competitive 65W 2C1A solution.
评论 (0)