Plessey Semiconductors Introduces LED-based Filaments

Plessey has launched its range of LED filaments. The company manufactured the LED filaments with its GaN-on-Silicon LEDs that it fabricates with the company’s MaGIC (Manufactured on GaN-on-Si I/C) technology. Plessey designed the filaments for what it describes as the surging filament bulb market. The replacement bulbs that employ LED-based filaments reportedly have vastly improved performance, but they retain the appearance of incandescent lamps.

Plessey points out that the conventional tungsten filament-based incandescent light bulb has been phased out in favor of LED technology. Plessey contends its Chip-On-Board LED filaments create the same amount of light while consuming less energy. They also offer a longer useful life.

The LED filaments feature unique terminations so that allow handling and spot welding by existing high volume fully automated glass lamp manufacturing lines. Additionally, the company incorporated a custom approach to controlling the current and Vf of the filaments to drive the filaments in a bridge configuration.

Plessey Semiconductors -PLF Series LED Filaments

Plessey’s CTO, Dr. Keith Strickland, said, “We have taken our existing Chip-Scale-Packaging technology, also used for our dotLEDs, into a revised format for the filament. Not only do we have an improvement in terms of manufacturability with GaN-on-Silicon and enhanced the power control for filament resistors, but Plessey will also be incorporating other active and passive electronic components for Chip-On-Board and Chip-Scale-Packaging solutions in next generation of filaments. Thermal performance and customization are key to our filament product portfolio, and Plessey remains committed to bringing to market unique LED products through our integrated approach to solid state lighting applications.”

The PLF series of filaments come in a variety light outputs, lengths, and color temperatures (CCT) from very warm 2200K to 6500K.

The company previously reported that it achieved 120 lm/W with its GaN-on-Si LEDs. It is not clear what efficacy its LED-based filaments could achieve in or out of a bulb, but some of the company’s LEDs do apparently have efficiencies of greater than 120 lm/W.