High current (SST-90) driver

[DIWdiver]

Hi I want to make two LED underwater torch using SST 90 LED. I have just two canister 9Ah Litium Ion, one with 3 cell and one with 4 cells. Can Your driver handel this voltage? If Yes can You sell me two?
Best Regards Ossi

If your cells are all in series (about 12V for the 3-cell pack, and about 16V for the 4-cell pack) then the driver can not handle those voltages. The maximum input voltage is 12V, and right off charge, the 3-cell pack would be about 12.6V, the 4-cell pack about 16.8V

If you have the 3 or 4 cells all in parallel then it would work but you probably have too little voltage to driver the SST-90 to 9A. The driver would protect the LED from overcurrent,but after a short time the current would start to fall, and the light would gradually dim as the batteries discharge.

You can run 4 cells in a series-parallel configuration, getting around 8V. The driver would handle this, and your light would be constant until the batteries were completely discharged, then it would suddenly go out when the battery protection circuits kick in. In this configuration, you would expect around 50% efficiency, which means the driver will generate as much heat as the LED, and would need the same kind of heatsink you need for the LED.

If you still want to order, I have some I can ship within a day or two of receiving payment. The sales thread is here: http://www.candlepowerforums.com/vb/showthread.php?t=264687

D

 

[curlyfry562]

Hey there is a nice instructable on this:

http://www.instructables.com/id/Circuits-for-using-High-Power-LED-s/

 

[bigterk]

I am working on a sst-90 lamp as we speak ! I will be powering the unit with a 18v pack , 2.5 amp low and 10 amp high sounds perfect for my unit. e-mail me contact info at [email protected]

 

[DIWdiver]

I have a bit of bad news for you, that my driver may not be suited for your project.

The IS1006 is a linear driver, which means if the input and output voltages aren't close, it dissipates a lot of power and the efficiency is very poor.

If you are talking about an 18V (15-cell) NiMH pack, you could run 4 SST-90's in series, and the voltages would work out not too bad.

But if you are talking about a LiIon pack, I guess that would be a 5-cell pack, and the actual voltage would range from 15-21V. At full power and full charge, that would dump over 60W into the driver. It's possible to manage that, but it's a challenge.

Either of these, you would HAVE to run it with 4 LEDs in series, which would mean dumping something like 170W into the heatsink, between the LEDs and the driver. That will heat it up FAST.

If you want to run only 1-3 LEDs, take a look at this driver instead. It's a switcher, and can handle the input/output differential much better.
http://www.candlepowerforums.com/vb...icient-5A-9A-Buck-Converter-for-SST-50-SST-90

Here's a link to a page that has a whole list of driver suppliers you could check out: http://www.candlepowerforums.com/vb/showthread.php?292465-DIVE-LIGHTING-LIBRARY