D.I.Y. Illuminated tailcap

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)

I use the 5.1 and 5.3 combo myself.

I use the stock with the light or in triples I use PD68’s high current switch board.

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.

Not sure if it’ll fix your issues, but here’s a post where he discusses it:

Exactly what I was looking for, thanks!

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. :slight_smile:

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.

In my case, the timings shorten so much that the light thinks the fastest half-press I can humanly do is too slow to even switch modes!

If you aer using the banggood drivers they use really bad OTC caps and this is quite common. You can replace the cap with a good X7R cap and it will vastly improve things.

Unfortunately, we can rule this one out :(. I’m using a nice X7R cap supplied by Richard. Timings do not shift at all when there is no lighted tailcap.

Then the bleeder and/or the tailcap current is not correct. With those properly set I do not notice any difference. If they are not right then it will effect things for sure.

I have found 560ohm bleeders to be the most relible myself as long as the tailcap current is kept below ~.3ma, I generally go for about .1ma

Yeah I can report the same using 470 ohm bleeders (cause that’s what came in my kit). Timings do shorten, but its not so much that I even notice it during normal usage. I have to be paying attention to notice the change.