UKE 2AAA led current regulatet ?

[artar]

Underwater Kinetics says on their website that the uke 2aaa led is current regulated ?
uwk 2aaa led

is this good or bad ?

 

[treek13]

[ QUOTE ]
http://www.uwkinetics.com/UK2AAAWLEDIND.htm said:
Built-in current rugulation circuit for constant light output and long lamp life


[/ QUOTE ]

What the heck is rugulation? /ubbthreads/images/graemlins/grin.gif

Now if it is truly current regulation, that would be cool!
Pat

 

[jtivat]

There does appear to be some circuitry in the head.

 

[Illuminated]

I think it qualifies as "semi-regulated". Down to 50% output after 19-20 hours, if memory serves. I think it was Quickbeam that did a nice review on it.

I have one, and I like it for the price.

John

 

[Doug Owen]

UKE 2AAA LED performance

I ran some voltage, current and light output tests for mine that might prove 'enlightening' (sorry, couldn't resist):

,8 Volts, 3 mA, 3 cp
.9 7.7 11
1.0 10 21
1.1 12 31
1.2 15 42
1.3 17 53
1.4 20 65
1.5 23 79
1.6 26 100
1.7 30 117
1.8 32 131
1.9 34 156
2.0 37 167
2.1 40 185
2.2 45 220
2.3 51 256
2.4 57 280
2.5 63 326
2.6 70 364
2.7 77 386
2.8 84 419
2.9 93 457
3.0 104 475
3.1 107 519
3.2 115 534
3.3 124 572
3.4 135 585
3.5 146 597
3.6 157 603

Several things seem clear, at least to me. Yes, there is electronics in there, no, it's not regulated (as it's normally defined) and under the 'time to half original birghtness' test 19 or 20 hours seems highly unlikely.

Let's assume 3.0 Volts to start, 100 mA more or less, 475 cp as I measured it. Half level is at 2.2 Volts, 45 mA. Let's assume an average current of say 75 mA from the two AAA cells. Average voltage is 1.3 Volts times .075 Amps is 100 mW load per cell. Using the Energizer E92 curve for 100 mW looks like a bit under 400 minutes to 1.1 Volts, under 7 hours, more like a third that time.

Doug Owen

 

[artar]

Re: UKE 2AAA LED performance

thank you all for clarification.

 

[Quickbeam]

Re: UKE 2AAA LED performance

I think it qualifies as a voltage boost or "step up" circuit which provides what is considered a "semi-regulated" discharge profile. AKA it drains the batteries better and faster than direct drive, but still has a sloping discharge curve.