Those three resistors (R270, R270, R33?) are most likely your voltage sense resistors. You can solder another one to the side of the small one (so it's easier to remove) and see what happens to current. There are formulas if you know the voltage drop across the bank, but I would just try adding one R3ish (.3 ohms) resistor at a time and remeasure current to the emitter.
A good way to rig the driver so you can add resistors and measure without reassembling the light is to solder wires to connect to your cells and then connect one of the LED leads to a DMM and then the DMM to the emitter. Here is an example. It's a little confusing because there is another driver piggy-backed in it. The fat Red and Black wires going straight up and out of the picture are going the cells. The L- wire is going down the DMM and then the DMM is feeding the emitter. Shorter wires reduce resistance losses.
Thanks for suggestion
Those R270 + R270 + R330 in parallel
according to parallel resistor calculator its about 0R095
I have measure current with clamp meter at high is about 2.1A
anyway how to make this driver have only one mode (high only) ?
No prob. Your calculation sounds right to me (little less than 1/3 of .3 ohms).
One mode is real easy if you can identify the MCU pin that is Vcc (+ input) and the pin for PWM out. You then just then add a jumper between the pins. You will no longer have LVP or thermal protection, if your driver even has those. You pull the MCU if you wished as it will be consuming a tiny bit of power, but controlling nothing.
This one use PIC12F629
If i remove that MCU it will always on to high mode?
I thought those IC that “drive” mosfet for buck regulation (sorry i’m new about MCU thing)
I had try remove all three resistor and replace it by 0R047 (since this only low value that i had), change SS54 to V8P10 diode, and change those 33uH inductor with a “bigger” one
Now, it draw 4,2A to Load, awesome :cowboy_hat_face:
The only 6 leg is near those MCU (wrote 4170a at the body) ?
and which one of pinout for PWM out at MCU, i already download datasheet but can not understand
Yeah, the MCU Pin used for PWM would be determined by the firmware.
I didn't see the other 3 legs of that component due to shadow in picture. I'm not familiar with that marking though. Could you clean up the driver with alcohol and then take a picture of each side with light behind it. It would make the traces stand out.
It looks like the top right Pin of the MCU (In 2nd picture) maybe the PWM out. The PWM out should go into one of the Pins of the Buck Controller and then a different Pin on the Buck Controller should feed the Gate Pin to your MOSFET. The Gate Pin of the FET should be the right pin when your looking at it with the big tap pointing up.
EDIT: I take that back about the top right pin of the MCU. I think I see a trace for that Pin also going to that Capacitor. Maybe that Pin is Vcc. Maybe better pictures will help answer some questions.
Which Pin does the data sheet say is Vcc? Is Ground the bottom right Pin per the data sheet?
Oh, that looks very nice. The tint looks much better at the current. Did you change the camera settings? You should be proud of that light. Really has a smooth beam profile. Congrats :)
I think your idea for using the scope is very good. I wish I knew how to use one. Check all the pins (except Vcc and Gnd) on the MCU and also on the 6 pin "buck controller".
This is what i got from my scope
Upper picture = Output MCU
Lower pcture = Mosfet gate input
Low Mode
Medium Mode
High Mode
Yes, you right ImA4Wheelr
Those MCU only “pull up” output to approx 5V (scope at DC coupled)
So if i jumper those pin to V+ (lets says i’m feed it with 15V supply), its will be fine ?
s
Camera setting still same, ISO 400 ; F/3.5; 1/4s IIRC
^ I agree with FF. You definitely don't want to feed 15v. You want the Vcc for the MCU which should be in the 3 to 5 volt range. Nice work. I need to learn how to use a scope.
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.