Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-Ion

Playing around with Li-Ion R123 and AAA, put one in my Dorcy AAA, fried the LED but FAST! Bummer, it was a 26K LED too.

Here are the stats

Dorcy with Li-Ion running a TWOJ: 500 ma at the TWOJ, .65 ma at the battery. Fairly efficient.

Nuwai: .59 ma @ the Luxeon, 1.15A at the battery. Wow, that's really a crappy driver.

I'll let you do the numbers, but it really argues for putting the Dorcy circuit in the Q3, perhaps using an H binned star instead of a J. As pointed out before, the Dorcy circuit isn't as hot as the Q3, but definitely more efficient.

Something doesnt seem right about only getting .59 ma at the Luxeon in the QIII, did you mean 0.59 A ? or 590 ma?

Ryan

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

He meant 580mA, or 0.59A.

Bill

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

yeah, my bad - my vom reads in amps, not ma...

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

cool, thanks

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

twentysixtwo,

I am looking to do the same when I get back. Thanks. Do you have any pictures of the internals of your mod? Also, how are you measuring current? Take a resistor and measure the drop across it?

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

My VOM is in-line for current (10A Max)

I simply disconnected one side of the star and completed the circuit with my VOM.

No pix yet - I was simply measuring the benefit of using the Dorcy AAA circuit. Some people had estimated the QIII Driver efficiency at 60% but it can vary with input and output voltage.

Here are the stats:
QIII Driver efficiency with R123/TWOJ: 51%
DAAA Driver efficiency with R123/TWOJ: 77%

Current & Est run time on a 700 mah R123/TWOJ:

QIII: 36 min, 590 ma @ emitter
DAAA: 56 min, 500 ma @ emitter

So if you have a Q3, you can get 55% more run time if you sacrifice 18% current which probably is less than a 18% drop in brightness.

Me? I'm defintely going to buy another Q3 and mod it. Now if I could only figure out how to get a 85%-90% efficient driver that could pump out, say, 750 ma with a R123 that will fit. Will the Nexgen BB do it?

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

Something is wrong there. You are using an R123 and not a CR123, and only getting 590 mA at the emitter? That is way low, and not characteristic of the R123/TWOJ/Q3 combination. I get about 600 mA at the emitter while pulling about 800 mA from a CR123. With an R123, current to the emitter is likely closer to 1000 mA. I suspect something is wrong with your methodology.

Still, the Q3 circuit IS inefficient.

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

wouldnt the R123 cell bypass the converter due to the voltage rules on the converters. I thought that a R123 cell basically bypassed the circuitry and goes direct drive to the emitter, at least on the QIII???

Ryan

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

IIRC, there was some discussion that there is a ripple in the Q3 curent, so perhaps a DC current reading is incorrect.

The Q3 gets warm after ~5-10 minutes, enought to make me think it's receiving at least 750 ma

Re: Nuwai Q3 vs Dorcy AAA Driver Circuits with Li-

Resistance of the DMM was added to the driver circuit when you connected the DMM in series with the circuit. The current flow reduced due to the higher loading resistance.