You got it bro. Jumper MCU pad for Pin 1 to the MCU pad for Pin 4. Keep or pull the MCU, which ever you prefer. Nice mod work tjeret. Great DIY attitude and initiative. Glad you joined BLF.
Any plans to increase current further?
EDIT: Wonder why Pin4 and Pin 5 have a jumper. Trying to look at the trace for Pin 5, but can't make it out. Are you counting the pins like this?:
Ok will try to remove those MCU
Those pin 4 and 5 already have a jumper as default configuration
i don’t know if output MCU can be parallel
yes i count like datasheet
Look like i’m good with those 4.2A
modification to heatsink for higher current will be PIT*
s
I accidentally pull a trigger for K40M couple week ago after testing the output Solarforce K3
because i thought this one will not be a good “thrower”
Hopefully it will arrive soon and will try to crank current little further
No need to remove on my behalf. It should be fine with it. If you do remove, I suggest a cheap hot air gun (not a hair drier. I think you know that but other readers may not). If you do, please try to get a back lit trace picture.
tjeret wrote:
Those pin 4 and 5 already have a jumper as default configuration
i don’t know if output MCU can be parallel
Me either. A good trace picture of each side would help.
tjeret wrote:
Look like i’m good with those 4.2A
modification to heatsink for higher current will be PIT*
Sounds good. I know where you are coming from.
tjeret wrote:
I accidentally pull a trigger for K40M couple week ago . . .
ah, huh, accidentally. I've accidentally pressed the "buy" button and accidentally input the payment information too. clumsy fingers.
Nice looking driver mod there. So the pad for Pin 5 goes to nothing. My guess is that Pin 5 on the MCU was the actual PWM out. So they had to bridge it to Pad 4 to feed the buck controller.
It was a real pleasure collaborating with you and FrickelFreak on these mods. You should be proud of your accomplishments on this light. You demonstrate some fine craftsmanship. Looking forward to seeing what else you come up with in the future.
I put back two 0R27, now current around 5.7A
with 1 minutes operating those tiny driver is very hot
Unfortunately still can not reach those K40M :_(
I’ll stop with 5.7A
Congrats again tjeret. Pushing the poor little driver hard now.
I'm not aware of any good buck drivers that get much over 5 amps that are under 26mm diameter. There are a couple great minds on BLF working on diy solutions for that but it seems to be quite a challenge.
That driver of yours looks quite small for 5.7 amps. What diameter is it?
This one have around 19mm diameter
Ok, what about linear regulator like parallel 7135 ? better than buck regulator ?
No problem, i can DIY a little bit
Someone that knows better will chime in. I think you have done well to pull 5.7 amps out to that driver. So that Solarforce K3 driver seems to be a pretty decent driver, potentially. But, maybe its the other mods you did to it that is enabling it to handle 5.7 amps. Either way, good on you :)
Hmmmm, 7135 does not seem to be a good option. They would have to shed tons of voltage (heat).
How large a diameter driver can you fit in that host? Or, do you mind moving the driver external to the head?
That a maximal diameter (20 mm inside host)
I thinking on external driver too, but i’m aware about high current
since i can not replace those “thin” cable to Emitter :~
any thought?
There are probably all kinds of option if you can go external. The HX-1175ba is one, but there may be others that are just as good or better. I've driven it to 11 amps to the emitter with 4S Li-ion without any problems (talking MT-G2). The large diode on it is only rated for 10 amps though.
Da*n, thats a very nice one driver :cowboy_hat_face:
I like no component at the bottom PCB. Tempted to buy it
but only can purchase in 5 pcs ?
s
Do you have a recommendation about “simple” buck IC Controller ?
i see those “six leg” is also driving fet
I don’t mind to made my own driver, since i have some of Low rds Mosfet and Schottky diode around
The most knowledgeable member I know of here regarding buck controllers is wight. He introduced me to the QX9920 buck controller which appears to be the most widely used one out there in budget buck drivers. It seems to be the same buck controller used in the HX-1175b. It is different than the one in your K3 driver due to obvious pin out difference.
That would be so cool if you built your own driver. I will be watching with great interest. You're getting in to territory that is well beyond my electronics knowledge base and I would love to learn from it.
Thanks for the link
Wow thats a very cheap buck controller
Yes indeed IC that used in K3 have different pinout as you said and different feedback voltage around 195mV
And i don’t like its freq, only 17.6kHz which seems to “low for most buck controller” i know
Well, the only drawback is make PCB layout
But I will try, it seems fun
But don’t expect a small factor.
I will use TO-247 package for Mosfet and Diode 0:)