Editing Light-emitting diode (section)

===AC-driven===
LEDs developed by Seoul Semiconductor can operate on AC power without a DC converter. For each half-cycle, part of the LED emits light and part is dark, and this is reversed during the next half-cycle. The efficiency of this type of HP-LED is typically 40{{nbsp}}lm/W.<ref>{{cite web|url=http://www.ledsmagazine.com/news/3/11/14|title=Seoul Semiconductor launches AC LED lighting source Acrich|publisher=LEDS Magazine|access-date=February 17, 2008|date=November 17, 2006|archive-date=October 15, 2007|archive-url=https://web.archive.org/web/20071015021634/http://www.ledsmagazine.com/news/3/11/14|url-status=dead}}</ref> A large number of LED elements in series may be able to operate directly from line voltage. In 2009, Seoul Semiconductor released a high DC voltage LED, named 'Acrich MJT', capable of being driven from AC power with a simple controlling circuit. The low-power dissipation of these LEDs affords them more flexibility than the original AC LED design.<ref name="IDA" />