STMicroelectronics Releases PFC Boost Converter with 800V of Startup Power

By Chad Cox

Associate Editor

Embedded Computing Design

September 22, 2022


Geneva. STMicroelectronics released its L4985A/B and L4986A/B power-factor correction (PFC) boost converters with 800V of startup ability and a core logic to relieve input-filter X capacitors when power is turned off.  This is to ensure maintaining IEC 61010-1 and IEC 62368-1 regulations. Both the L4985A and L4986A function at 65kHz while the “B” counterparts run at 130 kHz.

The L4986A/B comes with additional I/O pins to restrict the device when a user-defined limit has been reached, while all variants include an outer pin to begin idle for a decrease in power used.

For devices that must meet IEC 61000-3-2 requirements, such as home computers, gaming systems, and smart TVs, the L4985A/B and L4986A/B leverages an emulator to reduce total harmonic distortion (THD) in differing operating variables and provide stable power to LEDs.

To ease the mind, STMicroelectronics includes protections against overloading, failed feedback loops, errors in settings, and boost-inductor overload with prevention of RMS current.

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