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I'm looking at this LED power driver from a design, and I see it has inrush current speced as 190Apk/400us. Does that mean there's a 190A spike over 400us. That seems a little insane, how would ever control something like that to turn it on and off? Here's the datasheet

enter image description here

Or is that just a rate and I have to use something else to determine peak current?

confused
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  • That is the surge current into the input capacitors when it is first energized. – Daniel Dec 03 '15 at 21:45
  • If you switch at the zero-cross, you will probably not see a transient like that. – Daniel Dec 03 '15 at 21:47
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    That looks like a fairly normal peak inrush current. Examine a few bridge rectifier datasheets and note their Issm (surge current) ratings. To pick one low cost 10A one ... 200A for one cycle (>> 400 us) http://www.farnell.com/datasheets/1662105.pdf –  Dec 03 '15 at 21:48
  • So what does that mean though will I see 190A at 277V for 400us if I switched it over at the peak? – confused Dec 03 '15 at 23:34

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Yes, the specification is for inrush current.

If you look at section 3.8 of the data sheet you reference, the manufacturer calls for a type CCMR fuse (Little Fuse brand). LittleFuse mentions "withstand sustained starting currents".

enter image description here

http://www.littelfuse.com/~/media/electrical/datasheets/fuses/industrial-and-ul-fuses/littelfuse_fuse_ccmr_datasheet.pdf

Marla
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