Zener diode protection network in submount for LEDs connected in series

Patent · Tue Mar 19 04:00:00 EDT 2013

OSTI ID:1531848

Wei, Yajun; Collins, III, William D.; Steigerwald, Daniel A.

A transient voltage suppressor circuit is disclosed for a plurality (N) of LEDs connected in series. Only one zener diode is created for connection to each node between LEDs, and a pair of zener diodes (the “end” zener diodes) are connected to the two pins (anode and cathode pads) of the series string. Therefore, only N+1 zener diodes are used. The end zener diodes (Q1 and Qn+1) effectively create back-to-back zener diodes across the two pins since the zener diodes share a common p+ substrate. The n+ regions of the end zener diodes Q1 and Qn+1 have the highest breakdown voltage requirement and must be placed relatively far apart. Adjacent n+ regions of the intermediate zener diodes have a much lower breakdown voltage requirement so may be located close together. The zener diodes may be placed within a very small footprint or can be larger for better suppressor performance.

• Research Organization: Lumileds Lighting U.S., LLC, San Jose, CA (United States); Koninklijke Philips Electronics N.V., Eindhoven (Netherlands)
• Sponsoring Organization: USDOE
• DOE Contract Number: FC26-08NT01583
• Assignee: Koninklijke Philips Electronics N.V. (Eindhoven, NL); Philips Lumileds Lighting Company, LLC (San Jose, CA)
• Patent Number(s): 8,400,064
• Application Number: 12/556,054
• OSTI ID: 1531848
• Country of Publication: United States
• Language: English