Introduction

Traditional flyback architectures can no longer meet the requirements of high switching frequency, high power density, and high efficiency for high-power adapters. As a result, the LLC architecture, better suited for higher power outputs, has been introduced into 100W+ high-power adapters. This effectively improves conversion efficiency, reduces size, enhances portability, and increases product competitiveness.

Additionally, due to the use of large-capacity filter capacitors in rectified switching power supplies, which exhibit capacitive loads, significant high-order harmonics are generated during the charging and discharging processes, causing pollution and interference in the power grid. To address this, engineers have begun incorporating PFC (Power Factor Correction) circuits into switching power supplies. For power supplies exceeding 75-85W, PFC circuits are mandatory to improve the power factor and correct load characteristics.

In response to the current trends of high efficiency and miniaturization in adapters, MPS has introduced a range of PFC+LLC combo controllers to help manufacturers significantly enhance product integration. Recently, ChargerLab identified multiple devices equipped with MPS PFC+LLC controllers. The following article will provide a detailed introduction.

MPS HR1270

MPS HR1270 is the subsequent upgraded model of HR1211. It is also a multi-mode PFC+LLC controller. The built-in power-saving technology helps the power supply design achieve optimal efficiency in the entire operating range.

The HR1270 PFC controller also supports CCM/DCM multi-mode, high-voltage startup, and intelligent X-capacitor discharge. The LLC side also has a built-in 600V half-bridge driver, an internal integrated bootstrap diode, an operating frequency of up to 500KHz, and supports a variety of protection functions.

Application Cases

Pilot 140W GaN Fast Charger

This 140W gallium nitride charger from Pilot uses a folding pin design, which is easy to carry and store. The charger has three USB-C and one USB-A ports. The USB-C1 port supports 140W fast charging output and 33W UFCS fusion fast charging. The USB-C2 port supports 100W fast charging output. The USB-C3 and USB-A ports also support fast charging output and automatic power distribution.

Teardown of Pilot 140W GaN Fast Charger

Summary of ChargerLAB

ChargerLAB learned that the three chips launched by MPS, HR1211, HR1270, and HR1275, integrate LLC and PFC technologies, bringing new digital solutions for high-power power adapters and industrial power applications. The built-in digital cores of these three chips support UART interfaces, allowing engineers to program through an intuitive graphical interface, greatly simplifying the design process and improving product efficiency and reliability.

The chip mentioned in the article innovatively combines the PFC+LLC two-in-one design, which not only simplifies the primary circuit but also reduces the number of peripheral components used, making it a highly competitive power chip. At present, MPS's LLC+PFC chip has been adopted by high-power adapters of many manufacturers such as Microsoft, Momax, lifeme, and L Lab. It is believed that in the future, more high-power power supplies will choose to be equipped with MPS's LLC+PFC chip to achieve more efficient and stable DC output.