Optoelectronics
Power Integrations - Compact 25-Watt LED Lighting Ballast Reference Design Sized for T8 Tubes
Power Integrations today published a new reference design for a 25W LED T8 tube ballast power supply. Notable for industry-leading efficiency of greater than 91%, the design (DER-287) also meets commercial requirements for power factor (PF greater than 0.9) and harmonic distortion (EN61000-3-2 Class C). DER-287 is a single-stage converter built around LNK409EG, a member of the LinkSwitch-PH family of LED driver ICs. Single-stage technology greatly increases product lifetime by eliminating the opto-isolators and large aluminum electrolytic input bulk capacitors required by conventional two-stage solutions
Linktarget commercial and industrial lighting
Explains Andrew Smith, product marketing manager at Power Integrations: “Achieving very high power-conversion efficiency is as critical as LED choice in maximizing overall luminous efficacy of a lighting fixture. Efficiencies above 88% are extremely difficult to achieve cost-effectively in a T8 tube form factor unless a single-stage topology is used; this design easily exceeds 91%.” Smith added: “Most regions require either low THD or high PF in commercial and industrial lighting installations – specifications that the LinkSwitch-PH LED driver IC easily meets, enabling designs that can be used worldwide. Details are available in this new report.”
In addition to the highly integrated monolithic design that combines controller, driver, and switching MOSFETs into a single package, Power Integrations’ LinkSwitch-PH family features a number of protection features, including over-temperature and over-current protection. This means that very few external components are required to implement the solution – a very important consideration in compact T8 tube enclosures.