At the Lighting Fair in Tokyo, Japan (7-10 March), South Korean LED maker Seoul Semiconductor presented its new Acrich chip-on-board (COB) family of products targeting the high-quality and high efficiency lighting market
.“Seoul Semiconductor’s Acrich COB family is an entirely new LED concept, adopting its proprietary Acrich MJT multi-junction LED technology and direct AC technology on a COB platform,” says chief technology officer Nam Ki-Bum.
The new products exhibited at the Lighting Fair are based on Acrich technology, which is Seoul Semiconductor’s core LED technology for high-efficiency direct AC driven LEDs. Acrich COB has two line-ups: MJT COB and AC COB. MJT COBs use integrated multi-junction technology chips and have what is claimed to be the world’s highest luminous efficacy of up to 168lm/W. They come in standard form factors with a single power connection. AC COBs use direct AC driving technology, which combines four groups of LEDs in a unique, solderable design. This dramatically improves the simplicity in design and the lifetime of the product by eliminating the external AC-DC converter.
- The line-up includes 11 different MJT COB products ranging from 6W to 180W and 6 Acrich COB products that operate off 120V and 230V AC supplies.
- Seoul Semiconductor also provides various solutions such as optics and holders to aid manufacturing of lighting fixtures.
- In addition, Seoul Semiconductor has developed a high CRI (color rendering index) COB for spot lighting for broadcasting studios. The firm has applied its MJT COB technology to this product, yielding what is claimed to be the best performance in the industry.
- The MJT COB is a product combining multi-junction technology and chip-on-board technology, to which Seoul Semiconductor owns the corresponding patents.
- It uses integrated multi-junction technology, and is characterized by high light quality and reliability, says the firm.
The high luminous efficacy of 168lm/W, together with a correlated color temperature (CCT) of 5000K, a CRI of 80, a junction temperature of 85°C and 40W of power, is about 6% higher than that of existing products, the firm says. This high performance is achieved with an MJT COB that uses only 54 chips, compared with competing COB products requiring 144 chips, Seoul Semiconductor says. Also, MJT COB is claimed to be more reliable due to a significant reduction in wire bonds (a leading cause of defects in COB products).
The AC COB product line is driven by an AC source of either 120V or 230V. As it does not require a bulky and short-lived converter, the circuit cost can be reduced by about 25%, and it features good space utilization and a long lifetime, says the firm.
Both product lines are suitable for a wide range of general lighting applications requiring high-quality and high-efficiency indoor and exterior lighting applications including shop lighting streetlights, industrial and commercial lighting.
“In addition to the MJT COB and AC COB line-ups, we will also be launching two enhanced COB products this year, and we are going to market them worldwide together with all our high-quality LED solutions,” says Nam Ki-Bum.
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