Can this driver be modified into a FET driver?

This is a 46mm driver set up for a clicky switch. It is basically a giant NANJG board.

Can I turn this into a FET driver? If so, how would I attach the FET. I have some of the super low resistance ones from RMM Handy. I know I'll need to remove the AMC chips first, but need to know what to do with the FET.

Also, can I add a Zener diode to this board, and where?

There's a three extra wires that hook up to an external charge port. Ignore them, they'll not be used.

Same wiring as comfy’s Nanjg-092 tutorial I’d say. LED- hooks up to the meaty part of the FET. PWM (VDD) hooks up to the pin near the triangle. GND hooks up to the pin near the AA.

Is there ~6mm of height above the diver compartment? That all you need to piggyback a FET driver (BLF17DD or whatever one you have on hand). In the end much easier than trying to fit all the components on random pad’s with good connections.

Wondering if your diver already has voltage regulation for the MCU. Does that 3 pin component between V (+?) and V2- have a label?

I dunno Cereal — I don’t think it can get much more simple than than flipping the FET over, bending the legs down, and soldering one leg to GND and one to PWM. This board makes it easy with the plethora of pads. They are all easy to identify… as the legs of an AMC7135 face you VDD (which we use for PWM) is on the right. There may even be space to do it rightside up with no insulation…

ImA4Wheelr - good call.

The component you refer to is marked (jewelers loop) A1SHB.

I’m not experienced at this, but the board is big and easy to work on. I can hot air reflow too. I mainly want to know if I can convert it without flashing the whatchamacallit. I can’t do that. What is the component that needs to be flashed anyway.

Another question. I have a bunch more o these boards that are set for a momentary switch. Can FETS be used with momentary?
…and where would a Zener go.

Ya, ya, I know. This guys got a question for everything.

A1SHB is a transistor. I guess it’s for lockout during charging. So your MCU does not currently have a regulated voltage source. You need to zener mod (or something else, but it can’t be left alone for >1-series configs of course).

FETs can be used with momentary, but zener mod is not a good idea with momentary. It will quickly drain the cells and LVP will not have an effect on this. Protected cells will also likely be pulled low due to the relatively minimal current - the protection PCB often can’t stop slower drains.

The layout of the MCU section something of a mess IMO. If you want help on implementing the zener mod you’ll need to post a better picture of the front and a good picture of the back.

What exactly are you wanting a 3 independent channel driver?

With the direction by Mattaus (actually he corrected a massive cluster hump on my first try) I generated a 3x5*7135 SRK driver, it is for a busted 3*XM-L SRK I am going to convert to a 3*XP-G2 and run each emitter at 1750mA but wanted independent channels…didn’t release it because it a VERY specialized build and not a huge demand for something like that…people want bigger better hotter barn burners…mine would be a bit hotter than daily driver but make a SRK into a semi-thrower.

Good info wight. Thank you.

I don’t have any plans at the moment. I can set this board up any way it want. The board has three sectors. Right now sectors L1 and L2 are connected by the solder blob in the middle. If I wanted to connect L3 I just have to join the small pad beside it. If I want three separate sectors, I would remove the blob and all three would become independent.

I’m pretty certain that having 3 channels with a DD driver is just silly, assuming that 1 channel can handle all the current. Unlike 3 regulated channels, the DD driver will still dump current on the LED with the lowest Vf. This is generally not an issue with closely matched emitters, such as those from the same batch, based on our experiences here on the forum. Point being, no need to think about doing multiple channels. One FET gets the job done here.

Basically, the three sectors just make it a 3P board. With all the AMC chips removed, it gives you the option of 1P or 3P by the placement of a solder blob.

I’m not sure you understand my point. With DD that no longer matters. With 7135’s you ideally do not put the emitters in parallel, you keep them connected to separate channels - this way they each get their allotted amount of current through their allotted group of 7135’s. With DD they will pull current according to Vf, putting them in separate DD “channels” has no effect on this.

With the chips removed and driver changed to FET, wouldn’t it work the same as my 3P3S light?

You’re really starting to lose me. 3p3s is 9 somethings. Are you sure you are talking about 3p3s?

I was referring to This build
This is just a big NANJG board. If it was made into FET board, the three sectors would run parallel into three strings of 3 x XML in series.
I’m just using this as an example.

It’s hard to discuss this without a goal in mind. One size does not fit all.

What I’m saying is that there is no load balancing with a DD setup, so your only concern is total current. With your 3s3p example I guess we’d be talking about 15-20A. No need for more than one FET for that.

Is there anything making you repeat that this is a big nanjg board besides the fact that it uses 7135 chips?