CXW has launched a highly cost-effective 25W fully integrated PD fast charging solution, which can complete the entire 25W fast charging solution with only 3 chips.

CXW has launched a highly integrated 25W (Samsung) mini PD fast charging reference solution, which uses a flyback controller CX7530C with built-in switch tubes, a high-performance synchronous rectifier CX7538B with built-in synchronous rectifier tubes, and a protocol chip CX2919C with built-in VBUS switch tubes. The integration is very high, and only the above three chips, along with rectifier bridges and peripheral components, can complete all the functions of the adapter.

CXW is one of the few chip companies in China that can provide fully integrated solutions. Developing with fully integrated solutions can reduce the difficulty of adapter development, save component costs, and accelerate product mass production.

1、 Appearance of CXW 25W PD fast charging solution

The CXW 25W scheme adopts a stacked welding scheme of three PCBs, with a rectifier bridge and flyback controller chip CX7530C on the primary small board.

The secondary board uses a synchronous rectifier CX7538B integrated with MOS transistors and a protocol chip CX2919C. All functions of the secondary board are completed by two chips, with a simple circuit and simplified peripheral components.

The primary adapter adopts an integrated 650V switch tube flyback controller CX7530C, with an internal 0.65 Ω resistive super silicon switch tube, built-in soft start function, built-in slope compensation, and support for intelligent jitter technology to optimize EMI. It has ultra-low no-load power consumption, can output 33W under wide input voltage, and has lower temperature rise performance for 25W output.

The CX7530C has extremely comprehensive and excellent intelligent protection functions, including cycle by cycle overcurrent protection, overload protection, soft start, chip overheat protection, power supply undervoltage and overvoltage protection. It is suitable for small power switching power supplies such as PD fast charging adapters and smart Small appliance.

The adapter adopts a multi-mode synchronous rectifier CX7538B with an internal integrated synchronous rectifier tube, which integrates a 60V withstand voltage and a 12m Ω synchronous rectifier tube. It supports CCM/QR/DCM working modes and a maximum working frequency of 200KHz, with low static current. Compared with traditional Schottky rectification methods, it can improve efficiency by 2-6% and support 3 output currents.

The CX7538B supports a wide voltage range of 3.3-12V output, with only two capacitors as peripheral components. Coupled with the CX7530C controller, it can easily meet the six level energy efficiency requirements.

The CX2919C integrates VBUS switch transistor and output current sampling resistor internally, significantly saving PCB space compared to traditional solutions. In addition, the CX2919C is PD3.0 certified and supports 5V/9V/12V output, comprehensive fast charging protocol, built-in VPWR and VBUS dual discharge paths, and chip feedback support for line loss compensation.

The CX2919C supports USB PD and PPS, QC3.0/2.0 protocol, Huawei SCP/FCP fast charging protocol, Samsung AFC fast charging protocol, optocoupler and DC-DC feedback, and can be applied to PD fast charging and car charging mobile power supplies. The CX2919C is equipped with dynamic overvoltage/undervoltage/overcurrent protection, which monitors port voltage before starting output, D/D - and CC1/CC2 overvoltage protection.

CXW Launches High Cost Performance 25W Fully Integrated PD Quick Charge Package Solution

The bare board size of CXW 25W Demo is equivalent to that of Apple 5W.

The width of the CXW 25W demo bare board is equivalent to the diameter of a 1 yuan coin.

2、 Compatibility testing of CXW 25W PD fast charging solution：

• The CXW25W demo adopts a single C-port output design and uses ChargerLAB POWER-Z KT002 to test the output protocol. The CX2919C supports Apple 2.4A, Samsung 5V2A, QC2.0/3.0, Huawei FCP fast charging protocol, and also supports PD3.0 PPS fast charging protocol.

• The PDO message shows that CX2919C supports three sets of fixed outputs: 5V3A, 9V2.77A, and 12V2.08A, as well as two sets of PPS outputs: 3.3-5.9V3A and 3.3-11V2.25A.

• Using the CXW 25W PD scheme to charge iPhone 12, the measured voltage is 8.99V, the current is 2.39A, and the charging power is about 21.55W. Enter USB PD fast charging.

• Charge the Samsung S20 Ultra 5G phone with a voltage of 8.99V, a current of 2.45A, and a charging power of 22W. Enter USB PD fast charging.

• Charge the Redmi K30 Ultimate Commemorative Edition with a voltage of 8.53V, a current of 2.27A, and a charging power of 19.4W. Enter the USB-PD fast charging mode.

• Charge the Xiaomi 11 phone with a voltage of 8.92V, a current of 2.23A, and a charging power of approximately 19.9W. Enter USB PD fast charging.

• Charge the Huawei P40 Pro phone with a voltage of 8.98V, a current of 1.33A, and a charging power of approximately 12W. Enter USB PD fast charging.

• Charge the Samsung S21 phone with a voltage of 8.98V, a current of 2.43A, and a charging power of approximately 21.8W. Enter USB PD fast charging.