LEDs and Driver Boards, etc
- Thread starter TheBitterEnd
- Start date
TheBitterEnd
Well-known member
IDK, lets ask googleFulk said:
https://flashlightwiki.com/NiteCore
https://flashlightwiki.com/Fenix
Stuart France
Active member
Having made and used my own white LED lamps since the last century I've learned it can be hard sometimes to diagnose an occasional fault.
My current homebrew lamp has 4 chunky LEDs with lenses linked in series driven with a https://www.digikey.com/catalog/en/partgroup/4015-boostpuck-series/17014 driver all stuffed inside an old CEAG/Oldham style caplamp. The rotary on-off switch on the former miners caplamp has been replaced with an IP66 waterproof 5K pot which controls the gain of the driver circuitry. This knob allows me to select OFF at one extreme smoothly through a luminence gradient to full brightness at the other extreme setting. So none of this click twice for this or click and hold for that, etc, it works smoothly like a volume knob on a stereo amp, so quick to adjust and infinitely adjustable when transitioning between small to large passages.
The LEDS have been replaced a couple of times over the past decade when they got a bit old (or cooked) and better ones came along to buy. At the moment I have 2 whites and 2 warm whites linked up which makes nice shade of white for caves. Then it started behaving randomly.
It cut out momentarily then came back on. This got worse and more frequent. I tried changing each thing in turn to no effect. Then I noticed it tended to go out when I turned on my left side but came back on when on my right side. Reliability depended on angle of my helmet which had the battery pack on the back - that's the clue.
In the end I traced it to a faulty welded tag on a 18650 li-ion cell. The circuit was made when it was pulled together by gravity and circuit broken when gravity pulled the joint fractionally apart. Dependent on the orientation of my head. So I replaced the cells as they were getting a bit old too, and all is OK now.
I've now got trouble with a nearly new Petzl Duo Z2 that I won at Cavefest. I have it on another helmet. This is driven off 4xAA alkaline cells, rechargeables are not recommended. It worked fine for a while then one day it was bricked. Would not turn on when it worked fine the night before. I replaced the batteries twice with no effect. Then I left it with no batteries inside for a day and then put new ones in and it worked. Might be a microprocessor latch-up? Anyone got any ideas or seen this kind of thing before? Petzl have kindly offered to replace it, but as it works again now I've not taken up their offer yet, but I'm not comfortable with the idea of not understanding failure situations.
My current homebrew lamp has 4 chunky LEDs with lenses linked in series driven with a https://www.digikey.com/catalog/en/partgroup/4015-boostpuck-series/17014 driver all stuffed inside an old CEAG/Oldham style caplamp. The rotary on-off switch on the former miners caplamp has been replaced with an IP66 waterproof 5K pot which controls the gain of the driver circuitry. This knob allows me to select OFF at one extreme smoothly through a luminence gradient to full brightness at the other extreme setting. So none of this click twice for this or click and hold for that, etc, it works smoothly like a volume knob on a stereo amp, so quick to adjust and infinitely adjustable when transitioning between small to large passages.
The LEDS have been replaced a couple of times over the past decade when they got a bit old (or cooked) and better ones came along to buy. At the moment I have 2 whites and 2 warm whites linked up which makes nice shade of white for caves. Then it started behaving randomly.
It cut out momentarily then came back on. This got worse and more frequent. I tried changing each thing in turn to no effect. Then I noticed it tended to go out when I turned on my left side but came back on when on my right side. Reliability depended on angle of my helmet which had the battery pack on the back - that's the clue.
In the end I traced it to a faulty welded tag on a 18650 li-ion cell. The circuit was made when it was pulled together by gravity and circuit broken when gravity pulled the joint fractionally apart. Dependent on the orientation of my head. So I replaced the cells as they were getting a bit old too, and all is OK now.
I've now got trouble with a nearly new Petzl Duo Z2 that I won at Cavefest. I have it on another helmet. This is driven off 4xAA alkaline cells, rechargeables are not recommended. It worked fine for a while then one day it was bricked. Would not turn on when it worked fine the night before. I replaced the batteries twice with no effect. Then I left it with no batteries inside for a day and then put new ones in and it worked. Might be a microprocessor latch-up? Anyone got any ideas or seen this kind of thing before? Petzl have kindly offered to replace it, but as it works again now I've not taken up their offer yet, but I'm not comfortable with the idea of not understanding failure situations.
