BU_CK: TK61 driver, AVR controlled, utilizes both switches, up to 8A out

Hey guys, been working on this a while now. This is a drop in replacement for a TK61 and can be set up to 8A. The driver runs an ATTiny13A so anyone can flash the normal AVR FW (runs standard momentary switch FW such as "werner's UI" or "STAR-MOM") however there is also a second MCU, a PIC 10F322, this MCU runs very simply on/off code, its job is simply to cut power to the rest of the board since the MAX16820 chip doesnt have a low power standby (and also allows the second button to do a different function instead of just running them both in parallel to do the same thing), it will also have VERY LOW standby draw. The other reason for doing it like this is so no coding is required, any standard tiny13A FW can be ran and the second button will still function (the FW on the 10F322 simply turns a enable [non-PWM] signal on or off to the P-FET powering the rest of the board). Because of how simple the PIC code is you will never need to change that so I can provide the 10F322 MCU's for this for people who arnt yet doing PIC.

THESE ARE NOT READY TO ORDER!

This is the very first version, I'm happy with the progress (ratsnest = nothing to do and it passes DRC!) but I'm sure I'll need to make changes, plus as you can see the silkscreen is needing some attention right away.

All components on top! Components (if bought one set at a time) will be about $15 (good discounts on bulk tho) and the boards are ~$13 for a set so not the cheapest driver to build but should be worth it in the end. Another thing I plan to do is make the SW connections use the factory plug-in connector so you dont have to cut it off to solder (does anyone have a source for those so the original doesnt have to be removed from the factory board?)

The SOT-23 top left is a voltage regulator to power the 10F322 from the battery pack (I debated powering it from a coin cell)

below that is the 10F322, below that is 2 cap's

below that is the ATTiny13A

below that is a gate resistor on the MAX16820's DIN input

below that is the MAX16820 (the buck regulator)

Left DPAK is the power cut-off P-FET, right is the N-FET (AOD510)

Above the P-FET is a POWERDI5 package diode

top middle is the 2512 Sense resistor (surrounded by thermal via's) and the Inductor

Nice, Dan! I think I'm going to need one of these for my TK61. ;)

Cool, I don’t actually own (or even have in my possession) a tk61 so you can be my alpha tester.

Really great news, hope you finalize the product soon!

What’s the planned input voltage range?

Hi!

Why Vin is 12.6v? Any chance to work with 2 batteries?the TK61 work 2s2p this is so?

Thanks :slight_smile:

Nice, don’t Have a TK61, awesome either way, are the vias supposed to been unmasked?

Awesome, simply awesome!

What is the diameter and can it run 3 emitters?

See if these are Mini Micro ZH connectors.

Hm, I was under the impression the TK61 was 4p, either way it should still work with an XM/XP at 8.4vin and also allow 2p4s for 18350 16.4vin.

From other TK series carriers I’ve worked on it shouldn’t be much to make a few cuts, maybe add a piece of copper or move a spring and make it 4S anyway.

41mm, yea from 4s cells.

Digikey PN 455-1683-6-ND Look right?

How are you planning to get the P-channel FET to turn off? At 16V input, the lowest Vgs you’ll be able to apply is around 13V, which is well above the threshold for almost all FETs. Did you see my explanation of this issue in the emerald thread?

Looks right but you might confirm. DigiKey is good about sending out samples.

Maybe someone can confirm the 1.5mm pitch?

The keying slots look different. Also the TK has lowered sides on the side mounts:

Hoping this driver turns out well. Seeing as others were working on the HX-1175B, I have just put my original plans with the TK61 on hold due to having lots of other projects.

Im in for one if it turns of decent.

Will you be able to to have low voltage protection? Fingers crossed for zero PWM whine, and nice stable output that will not fry and XM-L2 at 8A.

TK61 carrier is 2S2P. It can easily be rebuilt to have all cells in series like I did on the TK75 R86 edition.

TK61 switch could also be rebuilt like I did on the TK75 R86 edition where one of the switches becomes a mechanical for a complete on/off power switch.

Hey, NightSpy, that my pictures! But its good. :p

Do you have pic’s of the mechanical switch mod? Didn’t see them in your thread, that would sure make things a whole lot easier (as would the cell carrier conversion, which I’ve done on several TK series carriers). Only problem is- you and I are crazy, we don’t have a problem doing that work, most people want a direct plug-n-play swap. If I was doing this for only me [First I’d be using a PIC instead of AVR] and secondly I would have a single MCU controlling everything, making this a plug in unit anyone can install and flash is my number one priority at this point (tho I’m not expecting to sell many of these anyway…)

I put literally hundreds of hours into this stuff, everyone talks it up but then in the end 3 people buy one and I end up loosing HUNDREDS of dollars in lost time and out of pocket testing expenses…

No, the pictures showing the switch mod was lost. Ive got two TK75 in pieces now, so I can take some pictures when I have rebuilt them in the same way. (Might take some time)

On the pictures you can see all the carrier mods.

You are right though, most people just want plug and play so if you can use stock carrier and no switch mods that would be the more attractive solution for most.

I would not bother making the switch contact plug and play. Fenix puts a lot of red stuff on it so its not always that easy to get out. I would say its easier to just cut the wires and solder them to the new driver (Anyone who does a driver change can solder some wires). It may be quicker and easier for the user as well as cheaper and easier to make the driver.

If your driver is a success it will probably be a better option compared to a HX-1175B based driver. So all the best wishes! No rush...

If this driver becomes a success in the TK61, im sure a similar driver can become popular in many other lights as well with a redesigned driver board. Im really curious if it will be able to output 8A without frying the emitter.

Id be happy to help you with a TK61, but shipping things across the ocean with tracking is expensive (around 45$ from me). JM or someone in the states can probably help you out with a light much quicker and cheaper.

Like the subject says, I’ll go for a package.
Doug