Also posted in another thread:
I was never able to do the lighting tailcap in triples with low voltage leds (new Oslon Square, Nichia 219C, XP-G3) in combination with BLF-A6 or bistro drivers. But now that I know the fix for the bistro driver (pyramid with C1, D1 and extra 5 Ohm resistor) the lighted tail can be done! . The above light has 4x219C and fixed X5/X6 driver from Banggood, 470 Ohm bleeder, 3x 4 KOhm resistors on the 6x dumb tail ring with red 0603 leds and red silicon cover.
I have not checked yet how the ‘fix’ +lighted tail works for the BLF-A6 driver in this same set-up.
I prefer Rev5.1 which is good for most of the Convoy single 18650 lights like S2+ and C8. Now I put in white leds on all boards and do the coloring with tailcap rubber’s color. Easy to swap colors if you bored with one.
Whatever comes in the light, usually. Unless you want a pot or something like that. The v5.1 board will work great with any mini-omten switch board (and others with some work)
What’s this fix you talk of? I ask as I have had lots of problems with getting the illuminated tailcaps to work in a triple 219C Convoy S2. The off timings go from normal to impossibly short (requiring faster and faster half-presses to switch modes) when it heats up.
Maybe I’m missing something obvious and my lights are borked too, but I’ve had no problems with Bistro driver triples and lighted tailcaps. Is it because I’m using Richard’s mtnelec driver or should I be more aware of some issue I may not be noticing?
So after reflowing a whole new DD+7135 driver (eliminating all parts but the LEDs as the source of the problem) and doing the X5/X6 driver fix with an extra resistor 10k resistor, the temperature sensitivity issue is STILL present.
I used a 750 ohm bleeder and 10k tailcap resistor driving 6 white tailcap LEDs which work normally (when flashlight is cold).
OTC values are: CAP_SHORT = 245, CAP_MED = 130 (I prefer a fast medium press time)
Out of curiosity, has anyone else experienced this problem? To test, get a feel of how quickly you need to half press to move up and down modes. Heat up the flashlight with turbo mode until fairly warm, then try switching modes again. If the issue is present, the flashlight will either switch down modes or not switch modes altogether.
My hypothesis is that the OTCs supplied by RMM [0805 1uF X7R Ceramic Capacitor] I’ve been using are heat sensitive and thus drain much faster than normal when hot.
The fix of the X5/X6 driver, as suggested by DEL, reduces the voltage spikes on the MCU and fixes the drop to low when switched to TURBO, and as I found out it (perhaps coincidentally) makes a lighted tailcap possible without screwing the UI. Reducing the temperature sensitivity of the driver is not mentioned for this fix.
As both drivers (Wight DD+7135 and mtn FET+7135) work fine without the X5/X6 fix, it must be unrelated. In any case, I didn’t notice a change between fix/no fix. Nobody else seems to have seen this temperature issue surprisingly. Maybe nobody with a lighted tailcap has driven their light hard enough to see it?
People mistakenly think it is bistro that is the issue when it is actually the X6 driver design that is to blame. That was before we started adding the extra components to fix the voltage spike issues. Namely the resistor before the diode.
RMM took a different approach, instead of stopping the voltage spike he bleeds it off via the zener diode.
These drivers work well with single higher voltage leds (i.e. the XP-L Hi in the BLF X5 and X6), the drop-to-moon problems arise with the newer low voltage leds (i.e. 219C, XP-G3), and possibly even just in case of triples/quads.
Ah, so it’s not me. Richard’s driver is better. Got it.
Also since it’s being discussed, my high powered lighted lights do exhibit some switch timing changes, like others have said. They get shorter, but not much. Really I have to be looking for it to notice.
Seems that the same temperature/heat issue has been reported before at page 23 of this thread. Seems odd why it only happens with a lighted tailcap. The workings of the OTC is strange beast indeed…
The OTC will be effected by heat with or without the tailcap. It all depends on how how the light gets and how well heat sinked the driver is to the body. In my pocket rocket the timings can change by as much as half.
This is why we are trying to do away with the OTC all together to completely rid ourselves of that issue.
. The above light has 4x219C and fixed X5/X6 driver from Banggood, 470 Ohm bleeder, 3x 4 KOhm resistors on the 6x dumb tail ring with red 0603 leds and red silicon cover.