Kai Domain P7 driver

[Packhorse]

Just got 2 of these drivers for P7 LEDs.
All seems fine with them except when I hooked one up to a 4.8v battery it started flashing. I assume this is a low battery warning since it is rated at 5.5 -15volt.
Thats fine. Im using a 7000mah 4.8v pack for my light but adding another cell is easy enough and I will then have a usefull low battery warning.


Next step was to hook it up to a 12v battery.
All went fine for a minute and then it started flashing again. This time it went from 2.7amp to .13amp off for .5 second .13amp then 2.7amp. and repeated this every 5 seconds or so. I felt the driver and it was quite hot.

So question time.
1. is it because the voltage is too high? I dont have a battery pack in between to test with at the mo.

2. Will heat sinking the driver help? One side is flat so I could paste a sink to it easy enough while the other side has the inductor. I could drill a hole in a sink so it fits around the inductor.

3. Can I run 2 P7's in series off of this driver?

 

[Packhorse]

1 more question while I am here.
If I have a 12v supply but V in max is only 9v but I want to drive 2 LEDs can I do it by using 2 buck drivers in series. I guessing not due to the first one will limit the current to the second and that one may require more current. eg if the Vf on the LED was diffrent.

 

[Der Wichtel]

I've read that this driver shouldn't be powered over 6V input voltage.
Otherwise it will get too hot.

Maybe your driver jumps to the flashing mode because it will protect the driver from overheating.

Read post number 152
http://www.candlepowerforums.com/vb/showthread.php?t=195358&page=6

 

[SUBjohan]

I have tested it upto 10V and worked fine for me.
My test results can be found here @ post #23

Greetz Johan

 

[StefanFS]

It works well on high with packs/cells around 6-8 Volt. It has memory, one of the circuits I got has no memory, the others have it, don't know why. Effiececy is low on low-medium levels with short runtimes.