Oshpark Projects

Thanks for sharing Scott!

Someone asked if the 15mm board had been tested yet and I had to say no. Figured it was time to get on this. The rest of you(Comfychair mostly) have been doing a ton of work on this project and I’m just doing what I can when I can.

My BLF17DD boards have been working great so far, both the first version without the ground ring on spring side and the second version. I already ordered some of the "2.0" boards with inline resistor pads. I have been running mine with a 200 ohm resistor in between the gate and MCU, also tried a 50 and 100 ohm which worked fine but had a ton of the 200 ohm already for zener mods. I think that 100 ohms is more in line with what may be ideal although 200 ohms if it works shouldn't hurt anything.

I haven't been using any pulldown resistors yet, are they really needed since we switch the power off on these at the same time we switch the PWM off?

Thanks for mentioning that. I used one of the extras from a Zener kit and it stabilized the modes nicely. The lower modes are too high and star 4 is all ahoo but default, blimkies, and low high work fine. Star 4 does 700, 800, 900, and 1500mA in the 4 modes with the 10440. Obviously the stock firmware is a bit inadequate for this use but the main thing was to confirm the operation of the FET and it certainly looks suitable for small lights.

[Quote=Mattaus]

Just one LED in the center of a 16mm PCB?

[/Quote]


We think it's perfect to put out torches by shooting. 16mm I think goes well!

XB-H

is a package 2.45x2.45 with 1.5Ampere from datasheet (XP-E 3.45x3.45)

Even XQ-E is interesting, maybe twists EDC

is 78% smaller than the XP-E! 1.6x1.6 datasheet from 1Ampere

I'm curious to try them both!

Thanks Mattaus!

CREE XB-H 16mm star

This is what you wanted, correct?

Perfect Helios! thank you very much, I believe that many users can make use of it!

a question, to improve the dissipation of the LED, it is not possible to add copper on top, connected to the base dissipating LED?

I can not figure out where mistake with eagle! work in the "board" but I do not get the parts "solder" as I would like!

Thank you!

I was thinking about adding copper on top but the via holes, in a way, cut off the heat path on top, directing the heat to the bottom instead.

Sorry, I don’t think I understand. If its a problem with exposed / uncovered copper, that is the “tStop” layer on top and “bStop” on bottom. Since eagle is so popular there are some nice tutorials around, videos too.

Now that I know which direction to use that little FET, I aim to attempt an application for my TP. I’d really like to be able to keep everything on the inside of the board if at all possible, this is a twisty after all with very limited space as everything was designed to fit together with little room for error.

That 1.5A on the Efest 10440 sounds VERY promising, exactly what I’d intended from the get go with this light! :slight_smile: (here’s hoping I can do this without screwing anything up!)

CREE XB-H 16mm with copper on top
Shouldn’t really provide much benefit if the bottom is attached to a heatsink / pill.

Should it have the little over flow channels on the actual led pads? Makes the pads look like “T’s”.

:ghost:
You can do 1.5A regulated inside 10mm, non-stacked. You just keep telling them to squeeze in a wee bit more. Promise them sweet copper for dessert if they keep the complaints to a minimum.

Yea, I noticed it was missing. You’ll see the actual oshpark link goes to a slightly different version then that picture was from.

The pulldown resistor is there to drain away any floating charge on the gate pin when the MCU is switching the PWM output on/off/on/off to get the less-than-100% modes. I thought someone had mentioned a while back that the tiny13 has internal puldown resistors to handle that and an external resistor isn't needed, but adding one definitely does have an effect, at least on the boards that have issues with mode switching.

I still don't understand why the 105C components+FET work fine without the resistors when on the Nanjg PCB, but don't work without them on the 17DD PCB. (that's when using the phase correct PWM only, adding resistors to the Nanjg might enable use of fast PWM on that one like it does on the 17DD)

Oh, I didn't post this earlier but I did test an original 105C diode in place of the Digikey ones, and it had no effect. So none of this is caused by incorrect diodes.

Ok, I’ll post it in the op after the triple XML.

Hey Dale, if you can, try it on one of the Oshpark Tiny10’s. If you cut the 7135 ground pad between the tab and the center pin you can solder the gate pin to the now isolated pad and use a 100 ohm resistor to jumper that back to the original pad.

Edit. Until it’s repeated, it didn’t happen or can’t be said to be reliable so let’s see if we can’t make it so.

Comfychair, can you update the shopping cart with the two extra R’s and I’ll swap them into the op?

Which value on the gate resistor? I tested a range of them and it's still not completely reliable even at 78 ohms, which makes me think 100 ohms may be cutting it a little close, I used a 130 on mine. Going too high matters too, more resistance there makes it less sensitive at the very bottom of the PWM values ('1' no longer works with even a 100-ohm at the gate, has to be '2' or above to light up).

I can try that Scott, will do today, but it won’t work in my TP. Pretty much have to have a contact only on the battery side of the board. The body is machined with near zero tolerance, if the contact to the battery get’s any longer from the board mount position, that will keep the battery tube from screwing in all the way and possibly cause a breach around the water resistance the o-ring provides.

I’ll build the Tiny 10 this way and check it out. Then if I can duplicate it, I’ll see if I can rebuild the PICcolo board for the TP. (fingers crossed, which is gonna make it difficult to do this board. :stuck_out_tongue: )

I defer to your experience here but it seems the lowest reliable value is in order. 100-130 is a place to start and it can be changed if needed. 10K on the other, correct?