06388393 is referenced by 124 patents.

Several types of ballast circuits for operating one or many LEDs in AC circuits finding particular use in aircraft lighting panels are disclosed. The first type is a linear transfer function ballast using inductors to limit diode current, and capacitors to ensure unity input power factors. The second type is a non-linear transfer function ballast using inductors to limit current, capacitors to ensure unity input power factor, and diodes shunted across one or many series connected inductors to steepen the transfer function. The aim of steepening the transfer function is to imitate the voltage—brightness characteristic of incandescent bulbs, thereby providing a direct replacement aerospace lighting solution compatible with existing AC light dimmers. It is also possible to configure the ballasts of the present invention to function with a DC input voltage.

Title
Ballasts for operating light emitting diodes in AC circuits
Application Number
9/526590
Publication Number
6388393 (B1)
Application Date
March 16, 2000
Publication Date
May 14, 2002
Inventor
Lewis Illingworth
Kensington
NH, US
Agent
Ward & Olivo
US
Assignee
Avionic Instruments
NJ, US
IPC
G05F 1/00
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