POWERQUARK ® Analysis of 65W fast charging reference design
After launching GaN direct drive chip and GaN integrated chip, domestic well-known fast charging chip manufacturer Southchip has once again launched the latest POWERQUARK® series of integrated switch power supply solutions for primary and secondary sides. The chip adopts Southchip’s self-developed fully integrated packaging technology and supports secondary control soft switch technology to improve conversion efficiency.
This chip integrates the primary-side controller of the fast charging adapter, high-voltage GaN switch, isolation communication, secondary synchronous rectification controller, and protocol functions. It has an industry-leading high integration level, reducing the volume of the charger and greatly improving the user experience of consumers. Below, ChargerLAB will analyze the Southchip POWERQUARK® 65W reference design to see the design of the scheme.
POWERQUARK ® 65W reference design appearance
The input end of the reference design for the Southchip POWERQUARK® 65W fast charger is equipped with EMI filtering and rectification small board, while the output end also has a small board soldered with USB-C output socket board.
The length of the charger measured is about 46.13mm.
Width is about 23.79mm.
Thickness is 27.56mm. The power density of this reference design can be calculated to be 2.15W/cm³ through these dimensions.
The net weight of the charger measured is about 46g.
PCBA module front view showing the left soldering of input board, right soldering of high-voltage filter capacitors, and the middle being a transformer. The right side is output filter capacitors and USB-C socket board.
The back side of the PCBA module in the reference design is soldered with the Southchip POWERQUARK® series chip and synchronous rectification transistors. This fully integrated chip designed by Southchip crosses primary and secondary sides, and has built-in high-speed isolated digital communication, no external optocoupler needed.
The input small board is soldered with a fuse and common mode choke.
The fuse specification at the input end is 3.15A 300V.
Side view showing a yellow Y capacitor soldered under the common mode choke.
The common mode choke is made with insulated wire wound around enamelled wire.
The X2 capacitor for safety is from KWOKTRAN
A rectification bridge is soldered on the side of the input small board, and on the back of the small board is a rectification bridge from Zhiwei Semiconductor with a screen print of R8M.
A discharge resistor for the X2 capacitor is pictured here.
The high-voltage filter capacitors are from AIHua.
One of them has a specification of 400V22μF, and the other two are 400V33μF, with a total capacity of filter capacitors at 88μF.
The reference design adopts the Southchip POWERQUARK® series fully integrated chip, model SC3107C, which has self-developed fully integrated packaging technology, and integrated secondary control soft switch technology and secondary control active synchronous rectification technology, and integrated multi-standard fast charging protocol compatibility technology. One chip can achieve the five independent functions of traditional charger controller, GaN device, isolated optical coupler, synchronous rectification controller, and protocol chip.
The Southchip POWERQUARK® series fully integrated chip has integrated devices that reduce the number of components outside the charger, providing advantages such as short development cycles and high product cost-effectiveness. The secondary soft switch technology reduces switch loss and improves conversion efficiency, which can be improved further with synchronous rectification technology to reduce cooling requirements. Additionally, it has built-in high-speed digital isolation communication without requiring an optical coupler for higher reliability.
The chip also has integrated protocol features that support UFCS fusion fast charging, PD fast charging, and private protocol customization to meet market demand. It also has integrated power overvoltage protection, cycle-by-cycle current limiting, output under-voltage protection, output over-voltage protection, output over-current protection, and output short circuit protection. It also has soft start with a maximum operating frequency of 175KHz. The chip is packaged in SSOP38L and supports PD fast charging applications ranging from 65W to 140W.
The transformer comes from Xinyuan Kang Electronics with insulating tape wrapped around the magnetic core.
Two surface mount Y capacitors are connected in series.
The synchronous rectification transistor is from Hengtai Ke Semiconductor with a model number HGN080N10AL, which is a voltage-resistant NMOS with 100V and a channel conductance of 6.5mΩ using DFN5*6 packaging.