I tried one Here and it seemed to work ok but I didn’t pursue testing because I didn’t want to accidentally damage an ‘expensive’ fet, while the cheap ebay ones didn’t matter so much. Well, it was expensive, now they are offering free postage grr.
HI all,
Once again it seems vesture is struggling to tread water in the shallow end.
I have used a lot of these drivers with the zener mod and they seem to work fine, but for some reason I have yet to be able to get a working single cell version.
Here is my board.
With this exact setup I get NO light what so ever. I built 2 identical boards to make sure it was not a bad component.
If I replace the 19.1K resistor at R1 with the 36K resistor used for the zener mod I do get light, but when I change modes into the higher up ones it stays there for a second or two and then cascades back down to the lowest mode.
I have tried this with 2 different firmwares and the results are very similar with each.
The boards and the FET are from Mountain electronics so they are proven components.
Any stab would be helpful :)
are the capacitors in the right place? C1 should have the bigger one, hard to tell from the pic
I agree it is hard to tell from the pic. Yes I did at least have that right :)
Hard to see, but are you sure that the C1 capacitor is the correct value?
How bout the diode - is it in the correct direction? A reversed diode would kill it. Also for LVP, I don't use the 19.1K, I use the 22K's as listed in the OP.
No, I'm not certain. The smaller one came from you, but the big one is mine from a batch of custom 7135 boards. That, the 19.1K resistor and also the diode were mine. Here is a pic of the PN.
Ahhhh- why is this board layout you have completely different from v024 in the OP? What is the board you are using?
What is this mystery board??? Anyone?
try using stock components for your first working board, it will also serve as control and only then you can experiment further… It may be a little too much troubleshooting otherwise… Just a suggestion, i had a few failures in a very similar way.
The board is from Mountain electronics.
Maybe the Y5V cap isn't cutting it? Those are the crappiest ones out there...but besides that, everything looks great. What you're experiencing sounds like what happens when the capacitor isn't there or is too low of a value. The DC bias derating on those caps is horrific.
Try a better capacitor (maybe from one of my pre-built boards?) and see if that changes how it works.
Vob try bypassing (i.e. shorting) the D1 protection diode and see if that clears it up, then get back to us.
EDIT: Upon further inspection MTN Elec board has the C1 cap placed correctly for 1S DD operation, my bad eyes, sorry.
For what it’s worth, I had similar issues with the single sided boards using components robbed from 105 nanjg’s.
I’ve had to go back to the original dual-sided fet boards until my order from RMM gets here with the better quality caps.
I use Samsung caps( they are cheap arround here, 1.3 euros for 100pcs) and i dont have a single issue so far
For those of us, that do have shipping issues with Digikey and Mouser( actualy shipping costs issues)
those A13 controllers are good
- they seem original, the price is only 40 cents - i already bought 30 of those and i dont have issues with them: several i reprogramed many times ( one of them over 30 times, my test board)
I got several or those from Nitro, they are branded V030, with two of them have an offtime memory issue, was thinking its caused by capasitors, but after changing them the problem still stays
Yes, someone answered that above. Technically, this is in the wrong thread because this thread is on wight's boards, not RMM's, but really doesn't matter - VOB is having problems and getting some good help so all is good here. I might have missed VOB's note in the post about being from MtnE.
The MCU link is good - cheap source. I got burned before though by ordering MCU's off of eBay from China where every single MCU could not be programmed. The date code was like from 2011. The seller refused to admit to any wrong doing but didn't understand anything about the MCU's. The batch he was selling were probably pre-programmed in a way to make them not programmable via the normal USB dongle method. Think it was $15 for qty 20.
thanks for the links, looks like a good offer on both, bought some 
Yeah Tom, you are right, but the Digikey US shipping is quite allright, for me its 60$….same with Mouser, Farnell got those at 2.5 euros per piece here( like 3$ )….and sometimes Farnell has hella wierd shipping policy, 2 years ago i ordered 25 cob emitters from farnell, and since they dont have them( in spire they claim they do) in the Uk warehouse they tried sending them from the US- 45$ shipping charge plus 190$ tax for handling and packaging( chips alone costed like 90$ i)…. :bigsmile: …i denied the order ofc
I found this chart on NXP’s website im just confused to say the least. I know 3R0’s are recommended and i have been using those, while there is a debate that 2R4-30YLDX (RMM’s choice) are better , there are even lower resistance ones out there, but they have higher capacitance? not sure if lower is better for our application.
Mosfet Selection Guide: At Page 83
http://www.nxp.com/documents/selection_guide/75017631.pdf