Toshiba Electronics Europe has announced the first devices in its second generation of LETERAS white light-emitting diodes (LEDs) made using a gallium nitride-on-silicon (GaN-on-Si) process. The company’s 1W TL1F2 LEDs are offerd as a cheaper alternative to current LED packages, allowing manufacturers of general purpose and industrial LED lighting to drive down costs.

The company advises that previously high-performance white LEDs were typically fabricated on expensive sapphire substrates in relatively small 100mm or 150mm wafer sizes. In contrast, the company claims it has developed a process that enables GaN LEDs to be produced using more cost-effective  200mm silicon wafers. This helps to reduce costs by replacing expensive sapphire substrates with more cost-competitive silicon substrates while making use of existing silicon fabrication facilities.

Offering a generational advance, the luminous efficacy of the TL1F2 white LEDs has been improved compared with the previous series. The company advises this is achieved by increasing the optical output power of the GaN-on-Si LED chips. The new series is claimed to offer a full correlated colour temperature (CCT) range from 2700K to 6500K, with minimum colour rendering index (CRI) values of 80 and 70 respectively. Typical luminous flux of the 1W LEDs ranges from 104 lumen to 135 lumen depending on colour temperature and CRI.

For easy design integration, the new devices are supplied in a standard 6450 package measuring just 6.4mm by 5.0mm by 1.35mm. Whilst typical driving current (IF) comes in at 350mA, with a typical forward voltage (VF) of just 2.85V helping reduce overall system power consumption. An operating temperature range of -40°C to 100°C makes this latest series suitable for both indoor and outdoor use in applications such as lamps, ceiling lighting, street lights and floodlights.