I think the forum messed up your notation there. It’s just like batteries. You have it correct.
VCC to ground measures 3.31V. No modes, only the dim output. Seems to me like something must be shorting somewhere.
Edit: Freakin blind now! I removed one of the LED’s from the circuit, the driver works fine, 3 modes, high kicked my ass.
Edit II: I have a loose MTG2 on Noctigon, brand new, got it yesterday…
Edit III: I also have an XM-L2 on a Noctigon mounted in an HD2010 pill backed by copper that is a test emitter, would I fare better using that?
That’s the correct voltage for the MCU of course.
- LEDs are wired correctly
- epoxy can cause electrical issues, make sure it does not bridge anything
- is C3 shorted?
I recommend that you do not operate it with only one XM-L hooked up at 4A. Consider my suggestion of making two sense resistors in series like this /\ That should give you a 2A drive current.
No shorts. Ceramic.
Look above, I pulled one of the emitters and held the positive to the single emitter and modes work, functions fine.
In response to your edit, no, an XM-L2 will be a little worse. Higher output wattage due to the higher output Vf but only slightly better efficiency. Reduce current or nothing at this point. When Mattaus get’s back on I want to see what he has to say, but frankly the LED2001 is looking bad to me right now if what I’ve been writing about the dissipated wattage limit is correct.
Just hook up driver + to one led and driver minus to the other led and led-( of the first led) to led+( of the second led)
or DL1, L1~~L2+, L2~~>D-.
Have you doubled up on the sense resistor yet? Matt suggested cutting the current until we find out what’s going on. No sense in popping $2.50 parts unless it tells us something useful.
wight- maybe they mean the cap to be bridging the two ground planes to dampen offset ground potentials. Filtering seems to be a big issue.
RBD, it seems that the two ground planes end up connected to BAT- in a matter of a few millimeters. That’s the part that I don’t really understand.
Ok, once again…
I have an XM-L2 U2 1A on a Noctigon and heat sinked connected to the Knucklehead. Emitter amperage is 3.81A, tail reading is 1.90A. (This is on high)
FWIW I’m explicitly telling you that I expect you to fry the LED2001 at that current.
Emitter voltage is 2.41, 2.55, 3.43V.
If you want, hookup the MT-G2 (which can’t be hurt by direct-drive from 2s anyway) and measure input and output current and voltage with the sense resistor you’ve got now (0.025 Ohms).
Once we have wattage for both of those things we can figure out efficiency and guess how much it will drop when we add a third cell. Please do not add a third cell yet.
So what to do now? The driver is working. The levels are there. I have a heat-sink on the regulator. Where to boss?
On it…
Hookup MT-G2 with 2s batteries. Get these measurements on high (I only care about high for this):
- input voltage
- input current
- output voltage
- output current
.12A, .56A, 3.70A initial readings from the emitter.
.08A, .55A, 3.50A at the tail.
4.71V, 5.01V, 6.43V on the emitter.
8.26V static
8.24V while on Low
8.12V while on Med
7.45V while on High
God dammit.
Edit: I'm taking a break from driver designing for a while. Anyone who spent money on this endeavor please PM me (Dale, wight, RMM). I'm insisting on paying for your troubles.
???
Pretty much.
91% efficiency w/ the MT-G2 on 2s. That’s bad in this situation.
I had this working. 3.8A to an MTG2 in V1. My measurements must have been off. I'm sorry.