Re: I prefer TLE-5 w/ SSC-p4 mod
I prefer the TLE-5 driver with the SSC-P4 LED. There's always a trade off between brightness and battery life. Terralux says that the TLE-5 draws 350mA to 450mA. I'm not sure if that is battery power or LED power.....but I will tell you that the 3 TLE-5's that I have, battery power is considerably less....around 240mA for battery voltage of 2.65v. And with a battery voltage higher, say around 3.00v, the current would be less.
That's because power in = power out minus the efficiency of the regulator circuit which is likely to be about 85% efficient for a buck/boost type regulator. The voltage drop across my USVOI SSC-P4 led was 2.16v on one of them and 2.22v on the other while the original lux 1w forward voltage was 2.24v, so they are very similar in voltage drop at the current that the TLE-5 is pushing through them, even though it is an 'I' bin voltage rating.
pwr in = .240x2.65 = .636w
minus the efficiency of the regulator: 15% of .636w = .0954w
yields pwr to the led of: .636w minus .0954w= .541w
with Vf of 2.16v, Led current is: .541/2.16v = .250 amps
The real advantage is that the SSC is way brighter for the same current....and thus you will get around 8 hours on a set of batteries for both the TLE-5 original and the TLE-5, SSC-p4 mod.
Terralux says the TLE-5EX draws 700 to 850mA. Again from my experience with the TLE-5, I believe this to be high but none the less, the TLE-5EX drives the SSC-p4 harder and you will get more light out of it but at less battery life.
So it's a trade off or a personal preference. I am going to be modding a dozen or so TLE-5's for guys at work and give them the option of TLE-5, TLE-5 modded or TLE-5ex. It's an easy mod but it does violate the warranty.
I didn't think it was very hard to mod the TLE-5. It just took me a few minutes. The hardest part was having someone hold the led still (and centered) while I soldered the leads. Next time I will center them all with a small amount of epoxy to hold them in place first. You do have to know which side of the led is cathode (-) and which side is anode (+) before you put it on or else you end up soldering it in backwards....but that's easy to check with dvm in diode mode. I just made sure that I knew what side was + and what side was - on the Terralux module before removing the LUX.
The other issue that I have with the TLE-5ex is possible heat issues. I ran the TLE-5 w/SSC-p4 continuously and after several hours it was warm but not so warm that I couldn't touch it. I am going to buy a TLE-5ex just because I want one and will interrogate it a little more to understand it. Heat may be an issue with it. However, most people really never leave their lights on continuously anyhow.
I will be doing more characterization on these in the next couple of weeks.
Jeff