Note: This is my first lighted switch on a non convoy driver.
When I put a battery in, it was acting erratic.
It was automatically cycling through config menu. After cycling through with no inputs, it settled on moon mode and would not switch through other modes.
I swapped in the regular tail switch and it was functioning fine.
I replaced the factory 300ohm resistors on the lighted switch with 4.7k resistors.
Now it functions and the illumination looks great, but I have no medium or long presses.
Build notes.
When I built the driver, I cut the center leg of the 7135 and installed a 680ohm resistor on the bleed pads.
This does happen for stock orange switches with some Convoy drivers, but doesn’t happen anymore after a resistor replacement. OP’s swap from 300 to 4.7K is more than enough to stop Convoy drivers from malfunctioning.
It seems that the issue is a bit more complicated because I’m not sure if these older FET drivers are designed for compatibility with lighted switches. I’ve heard of some folks needing to put in bleeder resistors, but sounds like you’ve done that too.
I don’t understand these FET drivers super well, but might suggest increasing the resistance even more (on either the bleeder or the LED resistor) to see if the malfunction stops. Or try a higher Vf color like blue, which was the standard color for tailcaps before Convoy introduced other colors.
Medium presses work now, so I am able to reverse modes, as well as get into hidden menu.
Long press does not work though.
So if I turn the light off in moon mode, the next time I turn it back on, it turns on in turbo, as if I had gone into the hidden menu.
This even happens if the light has been turned off for several minutes.
I’m assuming because it is bleeding voltage, it is keeping the OTC cap charged.
On top of that, the tailcap lights are a bit too dim now with the 10k.
I’m wondering if a smaller value OTC capacitor would make a difference.
Or maybe a pulldown resistor to the OTC cap.
I don’t really know enough to say if it would work or not.
I’ll give this a shot. Purple acted a little better than orange, but still wasn’t right.
ETA: I guess until I figure out a proper fix, I can just turn the light off in mode 2. That way when I turn it on, it will turn on in mode 1 (moon).
That’s better than getting unexpectedly blasted with 20 amps of turbo.
Thanks for giving this a shot. I looked up TA drivers but it appears that there are multiple models, some with 7 chips on the spring side and thus different from yours.
If your driver has a specific name/identifier, I would try looking up to see if there are documented successful mods for a lighted tailcap. If not, chances are that it is not designed for compatibility, and that substantial modifications are necessary.
I also tried red, cyan and green.
The red didn’t work at all. Possibly a bad switch.
Cyan and green behaved exactly as my orange after swapping to 4.7k resistors.
For now I’ll run with orange with 10k.
That way I get medium presses so I can go backwards through modes.
I’ll try a different bleeder on the driver in the near future. I’ll report back if I get different results.
For reference, I’m using the Texas Avenger OTC 1s build.
The number of extra 7135 chips differs based upon driver diameter.
17mm is fet+1+6
20mm is fet+1+7
22mm is fet+1+8
So on and so forth.
There are also other variations of the driver.
LDO, Zener model for multiple cells, OTSM, eSwitch etc.
I’ve been building the OTC (off time capacitor) models.
They run great for everything I’ve built thus far. Save for this illuminated switch issue I’m having.
I’ll get the illuminated switch figured out at some point, but for now here it is in 18350 mode.
The tailswitch is super dim with 10k resistors, but I like it.
These FFL351A 3700k neutral emitters are awesome.
Just a little bit of rose tint to them.
Most non-Convoy light switch friendly drivers need a bleeder resistor installed in order to function correctly which is placed between the positive and negative. The value of the resistor also varies, but usually is between 200 and 500 ohms.
Here’s what it looks like on a MTN FET+1 driver, which can be placed either on the front or back:
I swapped the tail switch resistors to 19k and all presses, short, medium and long are working 100%.
But as expected, the leds are very very dim.
I don’t think I have anything in between the previous 10k and 19k at the moment to try, but I’ll add some to my next digikey order.
Good notes, thanks!
Interesting development.
I added a 2k resistor between the main spring and ground. Which changed the Total Resistance to 507.4627 Ohms, from the 680 Ohms bleeder on the top side.
It actually made it a little worse. It added about 1 second to the total time the light needs to be turned off for it to not go backwards through the modes when turned back on.
ETA: the interesting thing is that once I got the switch side resistors up to 10k, all of the press times were perfect for short, medium and long. The only issue was reverse when turning back on, if the light were not left off for a short period.
I am assuming the OTC capacitor is remaining charged longer due to the bleeding.
It might be more work than you’re looking for but making some drivers that use the Bistro OTSM (off time sleep mode) could solve this issue as there’s no capacitor to worry about. Assuming it doesn’t mess with the MCU sleep mode though…
Off topic but I’ve been meaning to try and port Bistro to the attiny1616 to make some simple new drivers, I’m no embedded programmer though so quite a daunting task!
This is a great idea. I had thought about it but got a little confused trying to research it in the older threads. Some of them are thousands of posts long and kind of hard to parse through all the info.
I do believe I have all of the needed components. I just need to check on my ATtiny versions before building. I’ll probably got this route for my clicky builds, especially for illuminated switch builds.
I really like the Texas Avenger drivers. Even though they are now 10 years old, they are great.
