Reduced component costs and improved efficiency; meets eco-friendly standards for power supplies up to 250W.

STMicroelectronics supports power supplies and consumer products up to 250W in meeting strict eco-friendly design standards through power factor correction controllers that reduce component costs and increase efficiency.

STMicroelectronics (hereinafter ST) announced on the 18th that it has released the Transition Mode (TM) Power Factor Correction (PFC) controller 'L6462A'.

This controller generates a sinusoidal reference signal using a current generator and a current shaper instead of conventional voltage sensors and analog multipliers.

ST explained that this allows for the design of a boost PFC converter without an external voltage divider.

The L6462A detects the inductor demagnetization point at the gate driver output and adjusts the PFC conversion cycle, eliminating the need for auxiliary inductor windings or separate interface components.

ST stated that the standby current does not exceed 60µA, meeting the standby power regulations of the eco-friendly design standards.

Major Applications The fields include high-performance battery chargers, power adapters, and power supply units for home appliances and consumer products such as flat-screen TVs and lighting drivers.

In terms of operation, the L6462A operates in a valley switching mode, a quasi-resonant mode, to reduce power loss under maximum load.

When the load decreases, the operating frequency is gradually lowered through valley skipping to maintain efficiency, and a deep burst mode entry threshold is provided to support smooth dimming in LED lighting.

It is designed to accommodate an AC input voltage range of 90V to 264V and generally provide an output voltage of 400V.

The totem pole output directly drives an external boost converter MOSFET to supply a maximum current of +600mA/-300mA and is equipped with overcurrent, output overvoltage, feedback error, inductor saturation, and short-circuit protection functions.

The EVL6462A-250W-M demo board enables the evaluation of the L6462A's capabilities by implementing a 250W PFC pre-regulator that supports a universal input voltage range.

It achieves an efficiency of over 97% with less than 5% THD at maximum load and maintains less than 15% THD up to 20% load.

Operation modes and performance measurement results can be found in application note AN6380.

L6462A is currently being produced in SOT23-6L packages, and the price starts at $0.18 for orders of 1,000.