Looking for LED driver that can do 6A briefly from 18650 battery (3-4v)

lslonim

Other Parts Discussed in Thread: LM3409, LM3550

Hi, I am looking for a LED driver buck IC that can drive a 3V LED at 6A for 3 seconds, then under processor control, ramp down to lower currents after that. Power would be an 18650 Lithium battery (4-3.3v). I found a few parts that seemed likely but were out of stock. Can someone suggest a part for me that is currently available?

Thanks,

Lloyd

over 1 year ago

0 Mason Wang over 1 year ago

TI__Genius 9630 points

hello sir

may I ask the exact application here?

Actually we have device gap for low Vin and high current up to 6A. My suggestion is to have a two-stages where first stage is to boost battery voltage with a boost device, the second stage can use LM3409. As the min. input voltage for LM3409 is 6V, a boost stage is needed. It can support 6A with properly parameter setting.

0 lslonim over 1 year ago in reply to Mason Wang

Expert 1710 points

This is a special LED light that has to be powered by an 18650 battery, put out 6A briefly, and fit in a very small space. I don't think there's any way there will be enough board area for a boost stage. Since the 6A period is so brief (about 3 seconds) before we turn it down, maybe I can take a 4A or 5A design and just overload it for a few seconds to get my 6A?

0 Mason Wang over 1 year ago in reply to lslonim

TI__Genius 9630 points

hello sir

Going through the devices we have, I think the most suitable option is LM3550 supporting current up to 5A.

0 Mason Wang over 1 year ago in reply to Mason Wang

TI__Genius 9630 points

I will close this thread if no more questions.

Power management

Power management forum

Looking for LED driver that can do 6A briefly from 18650 battery (3-4v)