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Is the index "Startup Current" meaningful for an LED driver ?

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whitemoustache

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Every LED Driving Chip has such a index names "Startup Current" , for instance :
复制粘贴.JPG

But I really doubt whether this index is meaningful ?

First of all, no PCB designer told me its worth. In fact, a FAE even said that it has nothing to do with PCB design.

Secondly, I am very sure it is meaningless for the Lamp users to save their Charge for electricity. Take the IW3614 for example, if its Startup Current rises to 210uA, Voltage to 20V and startup time 1s (For easier calculation), and the user turns it 1000 times EVERY DAY, then 4 Kilowatt hour is saved in 10'000 years ....

One director tolds me that this index is meaningful for sales. That means, if a maketing guy notices your chip has a higher startup current than other chips, then he would ask for a lower price...

Does Startup Current has only such one funny meaning ? I'm really puzzled.
 

FvM

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You'll be able to answer the question yourself, if you read the datasheet "theory of operation section" thoroughly and understand how the chip works. Basically startup current has a well defined meaning related to circuit dimensioning. In fact it hasn't to do with PCB design, don't know where you got the idea.

In a short, your circuit must be able to supply the Start-Up current to Vin pin to allow the circuit to work. According to the datasheet, Rvin will be usually much lower than the value required by maximum Istartup.
 

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Is the datasheet in this website ? I didn't obtain it by GOOGLE....

You mean the index is important just because the Rvin is more easier to design ?...
 

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