I spent a couple hours playing with different LEDs and resistor values with very little success, basically, if you try to use different LED colors with much different Vf then the light output will vary significantly between them over the operating range of 3.7-4.2V. No combination of resistors for blue and red LEDs produced a consistent light output from each LED. Best results are obtained by using all LEDs of the same color (really more same Vf = forward voltage) IME YMMV.
If I had the Rev3 PCB and I want to use the Rev5b LED ring…where on the Rev3 PCB should I connect the positive and negative leads from the Rev5b LED ring?
Don’t feel stupid. The answer is - anywhere you can find the power. To be more specific, I’ve been tapping all my Rev5 ring boards directly to the switch itself, one lead on each side. One side of the switch is always connected to the battery’s negative and the other one is always connected to the body of the flashlight. Press the switch and the circuit is completed. I think the fact that one side of the switch is always connected to negative is pretty obvious. What may not be immediately obvious is that from this point in the flashlight circuit the body of the light, which we normally think of as ground, is actually connected to the positive “bleed” from the driver. You’ll have to do a bit of testing to figure out which side of the switch is which.
I’ve ran into an unexpected glitch with the S2+ build and the offtime based STAR_1mode firmware when using the lit tailcap. The driver will operate correctly when a battery is first inserted, but if I return and try some minutes later the light will not turn on unless I remove and replace the battery.
If I change to a standard (not LED lit) tail the driver operates perfectly all the time, so it has something to do with the lit tail. Any suggestions on what the issue may be or how to resolve? Will this still require a bleed resistor possibly?
By default yes, but there are extra traces so you can split the two sides of the board and have a different resistor value for each LED
edit: technically the order of the circuit (where the button is) is flipped around in your drawing, but it doesn’t matter for what I think the root of your question was
Based on my experience I’d recommend about 20kOhm. Blue has the lowest Vf of the ones I’ve used and benefited from the highest resistor value to appropriately dim.
Update: Added a 510mOhm bleed resistor on the driver and it operates perfectly now. I thought that the offtime based firmware should not require a bleed resistor for operation ?
Hey all. The clear S2+ gaskets were waiting for me yesterday when I got home. Now I just need to pick up some stamps. I haven’t really mailed anything in a while. I’m going to send some out in the next few days and I’ll see if I can get Richard to take some so he could just throw them in if you happen to be in the US and ordering something from Mountain Electronics. They come in a sheet like below so you just need to pop them out. Hopefully these will make the glowing S2+ tails a little better.
I received some clear gaskets yesterday (thanks J-Dub!) including a few extras. If anyone needs one please let me know and I’d be happy to drop some out in the mail :).
Now to get some PCBs on order. I believe it should be Rev5.1b for 14mm boots and I just use this above the stock switch in place of the metal washer? Which ones would you recommend for modding a S2+ metal boot tailcap?