Just received my LS and must say, I'm very impressed. The opportunities for unique LED flashlight design are at a new level.
I have been running the LS on a single 1200Ma
rechargeable 3.6v Li-ion battery. This seems like an almost ideal voltage and current combo for the LS. Only drawback is the rechargeable aspect of the battery and I'd like to utilize the LS in several 3 and 4 cell applications.
Looking through this forum I found several people using the National LM2621 Eval board for 3 and 4 cell applications. Something I'd like to do play around with myself.
I went to National's website to order a couple of EVAL boards and found that they are out of stock. I wrote to National, inquiring if the boards are going to still be available and have yet to receive an answer. Has anyone else had to wait on arestock?
I decided that there must be another solution besides the LM2621, so searched the net. I found something that might be of interest. I don't know if this has been discussed in other topics in the past. But, here is something that might be of use for an LS in a 3 or 4 cell design as well as for powering large arrays of regular LEDs.
It's a Laser Diode Driver Module that has an input of 3.0 to 6.0 VDC and the constant output is current adjustable (thru a pot)
in the range of 0 to 1.2 amp. The board is small, 14 x 35mm. This particular module is designed for laser diodes that do not
utilize an internal photo detector to adjust the output current. The pinouts are for 'DC In' and the anode and cathode of the driven
device. The specs on this board are very limited and my knowledge of electronics is even more limited. Therefore, perhaps some of you technos can take a look and lets us know if this driver can be used for powering regular LEDs and the LS. I don't know if the output is oscillating or not and have no idea if this is a practical or efficient
circuit to use as a replacement to the LM2621.
If someone cares to take a look the URL follows. I'm keeping my fingers crossed on this device because it does look promising in
the fact that it's cheap ($15.00), it's small, and adjustable without modifications.
The companies web address:
http://www.roithner-laser.com/
The datasheet on the device:
http://www.roithner.de/All_Datasheets/Drivers%20for%20Laserdiodes/EU38.PDF
Mercator