Led Design Guide Page 11 LED Design Guide

2015 Littelfuse LED Lighting Design Guide www.littelfuse.com LED Lighting Design Guide Part Selection Matrix for LED Lamp Protection It's important for engineers to avoid the trap of trying to use the same protection devices for every LED lamp assembly they design. Each application should be evaluated based on the operating environment, circuit operating parameters, and the pertinent surge protection specifications. Table 1 lists several Littelfuse part numbers for fuses, MOVs, and TVS diodes that could fit many of these applications and their associated surge test requirements. Transient Surge Spec Fuse Options MOV Options TVS Diode ENERGY STAR Program Requirements for Integral LED Lamps (for USA) 1. ANSI/IEEE C.62.41-1991, Class A operation. 0.5s 100kHz Ring Wave, 2.5kV, 7 strikes common and differential modes 047001.5 (1.5A SMT 1206 125V) 0453001 (1A SMT 2410 125V) 0454001 (1A SMT 2410 125V) 0473001 (1A Pico 125V) 39211000000 (TE5 250V 1A) 38211000000 (TR5 250V 1A) V150LA2P V175LA2P V240ZA05P P6KE300CA SMAJ400A SMAJ440A SMBJ400A SMBJ440A 1.5KE400A 1.5KE440CA IEC 61547 Equipment for general lighting purposes - EMC immunity requirements (for Europe/ Asia / Australia) 1. IEC 61000-4-5 Surge Immunity Test. For lamps < 25W: 1.250s/820s combination wave 500V/250A line-to-line test (10 strikes, 5+ at phase angles 90, 5- at phase angle 270) 0876016 (3.6x10 250V 1.6A) 39211000000 (TE5 250V 1A) 38211000000 (TR5 250V 1A) 0476003 (SMT 2410 250V 3A) 0465001 (SMT 4818 250V 1A) V300LA2P V320LA7P P6KE300CA SMAJ400A SMAJ440A SMBJ400A SMBJ440A 1.5KE400A 1.5KE440CA 2. IEC 61000-4-5 Surge Immunity Test. For lamps > 25W: 1.250s/820s combination wave 1000V/500A line-to-line test (10 strikes, 5+ at phase angles 90, 5- at phase angle 270) 0877002 (2A 250V 3.6x10) 39211600000 (TE5 250V 1.6A) 38211600000 (TR5 250V 1.6A) 046501.6 (250V SMT 4818 1.6A) V300LA10P V320LA10P P6KE300CA SMAJ400A SMAJ440A SMBJ400A SMBJ440A 1.5KE400A 1.5KE440CA NOTE: MOVs were tested with 1.250s open circuit voltage waveform and 820s short circuit current waveform forming a combo waveform with 2 ohm source impedance. Standard method was used for testing the MOVs per datasheet specifications which consisted of driving relevant surge current through the part with the generated combination wave. In real world events, actual peak current through the lamp with typical circuit impedance path will likely be lower. Littelfuse has tested the above part selections to a more stringent level as it complies with our internal testing standards. Table 1. A sampling of Littelfuse devices designed for LED lamp surge protection. Part Selection Matrix for LED Lamp Protection 11

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