The L6462A transition-mode (TM) power-factor-correction (PFC) controller cuts bill-of-materials prices whereas enhancing effectivity. Because of this, client merchandise and energy provides as much as 250 W can meet stringent eco-design requirements in high-end battery chargers, energy adapters, and energy provides for home and client merchandise like flat-panel televisions and lighting drivers.
The controller, developed by STMicroelectronics, makes use of a present generator and shaper to provide a sinusoidal reference as a substitute of a standard voltage sensor and analog multiplier, allowing boost-PFC converters with out exterior voltage-divider parts. This enables it to coordinate the PFC conversion cycles by sensing inductor demagnetization by way of the gate-driver output. Therefore, it requires no auxiliary inductor winding or interface parts.
The L6462A’s totem-pole output delivers as much as +600/-300 mA to immediately drive exterior boost-converter MOSFETs. It will possibly function on a large AC input-voltage vary, from 90 to 264 V, and is usually designed to ship a 400-V output voltage. An enhanced error amplifier and high-accuracy voltage reference sharpen dynamic response to large-load transients and stop extreme output overshoots or undershoots.
At full load, the L6462A operates in quasi-resonant mode (valley switching) to attenuate energy dissipation. Because the load is lowered, valley skipping progressively lowers the working frequency to take care of effectivity. As well as, the controller has a deep burst-mode threshold that ensures easy dimming in LED-lighting purposes.
The progressive present shaping and demagnetization sensing minimizes whole harmonic distortion (THD) and enhances effectivity, notably at intermediate and lightweight hundreds the place its idle present is beneath 60 µA.
Designers can consider the L6462’s options utilizing the EVL6462A-250W-M demonstration board and an accompanying software observe, AN6380, which describes the board’s working modes and efficiency measurements.
The controller, housed in a SOT23-6L package deal, is in manufacturing now, priced at $0.18 for orders of 1.000 items.
Go to https://www.st.com/l6462a for extra info.
