Onsemi introduces a new high power totem pole PFC controller

     Onsemi introduced the latest mixed signal controller, which is dedicated to the bridgeless totem pole power factor correction (TP PFC) topology. The target application of NCP1681 is ultra-high density offline power supply. The new controller builds on the success of the NCP1680 for designs up to 350 W, extending the power capability to the kilowatt range.

     In the past, MCU was required for TP PFC design, which increased the complexity of design and required coding. Now with NCP1681, it is only necessary to add some external devices and realize a fully functional TP PFC scheme without coding, thus saving time, cost and space occupation.

     Robert Tong, senior vice president and general manager of onsemi Computing and Cloud Division, said when talking about the launch of the new product, "The new NCP1681 extends the advantages of codeless TP PFC design to higher power. This enables our customers to continue to improve their design energy efficiency, while reducing design time and cost, so as to quickly provide solutions to the market."

     NCP1681 can be configured to operate in fixed frequency continuous conduction mode (CCM) or multi-mode, and the controller can naturally switch between CCM and critical conduction mode (CrM) to achieve optimal performance at various power levels.

     The new NCP1681 high power TP PFC controller combines mature control algorithms and novel functions to provide a high performance and cost-effective TP PFC scheme, and can also meet challenging energy efficiency standards, such as "80Plus" or "CoC Tier 2" requirements to provide high energy efficiency standards within a wide range of loads.

     The new NCP1681 is applicable to higher power supplies in the range of 350 W to several kilowatts. It operates in a general-purpose power input (90 - 265 Vac) and is widely used in applications including servers, high-performance computing, telecommunications, industry and OLED TVs. Under high voltage input, the energy efficiency of NCP1681 TP PFC scheme will reach nearly 99%.