STMicroelectronics launches L4983 PFC controller for CCM power supplies

STMicroelectronics has introduced the L4983 power-factor correction controller for continuous conduction mode designs in switched-mode power supplies from several hundred watts to multiple kilowatts. The chip targets higher efficiency, fewer external parts and stronger protection for industrial, medical and server-class power systems.

Why it matters: - The L4983 is designed to simplify continuous conduction mode power-factor correction circuits with very few external passive components. - The controller targets switched-mode power supplies from several hundred watts to multiple kilowatts, where efficiency, power quality and protection are critical. - The device is built to help systems meet efficiency guidelines and harmonic-current limits used in global power-adapter and equipment standards.

What happened: - STMicroelectronics introduced the L4983 power-factor correction controller for CCM PFC designs. - The device uses a proprietary multiplier emulator and distortion-optimization circuitry. - STMicroelectronics also announced the EVL4983-350W demonstration board for development with the L4983. - The company said two L4983 variants are in production now in an SO-8 surface-mount package.

The details: - The L4983 uses a totem-pole output with 7A sink and 3A source capability. - Typical applications include industrial and medical power supplies, high-power luminaires, servers, PCs and home electronics. - The controller is intended for designs that must meet EN 61000-3-2 and similar standards worldwide, including the Japanese JEIDA-MITI standard. - The device includes three power-saving modes. - Burst mode stops switching during light or zero load and resumes quickly without soft-restart as load increases. - Idle mode is pin-controlled, suspends switching and turns off the internal error amplifier. - Disable mode stops the device and resumes through soft-start. - Protection features include overvoltage protection, cycle-by-cycle overcurrent protection and inductor-saturation detection. - Line feedforward helps stabilize output power as AC input changes. - The controller checks voltage-feedback and current-sense signals at startup to guard against feedback loop failures. - Soft-start limits inrush current and helps maintain output-voltage regulation. - The EVL4983-350W board implements a 350W PFC pre-regulator with universal input-voltage range. - The demonstration board provides a regulated 400Vdc output. - STMicroelectronics said the board delivers low total harmonic distortion across the load range and 97.4% efficiency. - The L4983A switches at 65kHz. - The L4983B switches at 130kHz. - Both versions are priced from $0.80 in 1,000-unit quantities. - A product page is available More information.

Between the lines: - The mix of low-power modes, protection features and two switching-frequency options suggests STMicroelectronics is aiming at designers who need flexibility across efficiency, acoustic, thermal and compliance trade-offs. - The demonstration board helps position the L4983 as a faster path from evaluation to final power-supply design. - The emphasis on harmonic distortion and global standards signals demand for cleaner, regulation-ready power architectures in higher-power systems.

What's next: - Designers can evaluate the L4983 through the EVL4983-350W board and start integrating either the 65kHz or 130kHz version into new power-supply designs. - Production availability and low unit pricing may support adoption in industrial, medical and computing power supplies. - Further design-in activity will likely focus on meeting efficiency and EMI targets while minimizing external components.