LED driver aimed at 100W incandescent bulb replacements

Power Integrations has unwrapped the DER-323, a reference design for an 18W, 88 percent-efficient, non-isolated A19 LED driver based on LNK460VG, a low-profile IC from the company's LinkSwitch-PL family. According to the company, the design is geared for a 100W incandescent bulb replacement and is optimized for low-line (90-135VAC) operation. The circuit is low-cost, requiring only a simple single-sided board and 25 components. No potting is necessary and the transformer is replaced by a low-cost inductor.

DER-323 uses a simple buck-boost converter topology that fits easily inside the A19 bulb. The design is EN61000-3-2 (C) compliant and has a high power factor of over 0.98, easily satisfying commercial and consumer compliance requirements, stated the company. Because LinkSwitch-PL ICs combine both PFC and CC converter functions in a single-stage topology, no electrolytic bulk capacitor is required, resulting in a very long operational life.

"The lighting industry typically asks for 80 percent efficiency for drivers targeting 60W A19 bulb replacements. To achieve viable LED-based replacements for 75W and 100W bulbs, much higher efficiency is needed in order to reduce the heat dissipated by the driver. The 88 percent efficiency of DER-323 satisfies this need and makes the thermal design of the bulb straightforward and inexpensive. DER-323 is also compact, reliable and easy to manufacture thanks to its low component count, single-stage architecture and use of a low-cost inductor rather than a transformer," noted Andrew Smith, product marketing manager at Power Integrations.