Single-stage power factor correction reduces component count in offline LED drivers
1 min read
Power Integrations has announced two new ranges of TRIAC-dimmable, single-stage, power-factor-corrected LED driver ICs targeting solid-state lighting (SSL) applications.
LinkSwitch-PH (optimised for isolated systems) and LinkSwitch-PL (optimised for non-isolated systems) are designed to deliver flicker-free monotonic TRIAC dimming and a user experience similar to that provided by incandescent illumination.
The LinkSwitch-PH and LinkSwitch-PL product ranges feature integrated single-stage power factor correction (PFC), which Power Integrations says enables SSL luminaires to achieve PF > 0.9. LinkSwitch-PH devices incorporate primary-side-control technology, which eliminates the optocoupler and supporting components used in traditional isolated flyback designs. Non-isolated LinkSwitch-PL designs are said to further reduce component count.
Both IC families are monolithic – incorporating the controller and mosfet onto a single silicon die – which simplifies pcb layout by minimising component count and eliminating parasitics between the controller and power mosfet. The new LinkSwitch products are optimised and operate at input voltages up to 305VAC.
Power Integrations' primary-side-control technology, featured in LinkSwitch products, is designed to eliminate the optocoupler, and the new LinkSwitch LED driver IC product families do not require the use of electrolytic bulk capacitors. According to the company, designers using the LinkSwitch-PL and LinkSwitch-PH for SSL products can expect the operational life of the driver to match that of its accurately controlled LED array.
Bill Weiss, lighting business development manager at Power Integrations, said: "Both new product families are ideal for space-constrained LED drivers used in replacement lamps. The LinkSwitch-PH family, optimised for isolated designs and rated up to 50W output power, is also exceptionally effective for external LED ballasts, often used in downlighting, architectural lighting, signage, and outdoor lighting. These ICs enable designers to optimise system efficiency and meet or exceed all regulatory standards, such as ENERGY STAR and EN61000-3-2."
