+1 w/finges. I've bee doin this stuff so long - there's so much history here, I make assumptions along the way.
C1 has been 10 uF since the beginning - last 3+ years, never changed, until the 25/45/85 came along and we(me) experimented with beefing up the cap. I go as high as 20 uF sometimes, stacking caps adds uF. Found it's needed on some boards, maybe with some parts, dunno.
I would also "always" populate R6 on the v032 board for a 25/45/85. I've used 12K's, but can go as high as 47K -- the lower, the more effective but don't go below 12K - some recommend not going below 40K.
Voltage divide resistors using batt+ after the diode should be 19.1K, before the diode should use 22K - that's been the rule so we don't have to use different values in the firmware. This board is before the diode, so you should use 22k so as not to impact the LVP values in all flavors of firmware out there.
This has been the "rule" for a long time now. Wight's boards are, I think, always before the diode. The diode causes a voltage drop, and that's why the difference.
If you mix it up, then the onus is on you to change the LVP values in the firmware - not sure if any firmware is around that configures it both ways, and allows you to choose at compile time -- could probably be done though, but you do want your voltage range you monitor roughly centered in the range you read in via the A-to-D.
Apologies for bringing up an “older” thread - I am looking to build a Fet+1 17mm Attiny13 driver which is one-sided and works with common firmware (like the ones in the repository, I have all flashing tools here). Initially I was going to order the MTN-17DDm (v1.11) from MTN, but realized that international shipping for 1 PCB (which is 0.65 cent) would not be that efficient.
Is OSH Park ~ comparable with the MTN 17DD v.1.11 and would that be the current PCB version to use? Would anybody know whether that board works out?
I already own the following parts - do I need anything else? It is for a 1s configuration, so no Z1 required, I guess.
attiny13a-SSU
C1 - 10uF 10V+ 0603 or 0805
OTC: 1uF 0805
7135 (380 mA)
R1: 19.1k 0603
R2: 4.7k 0603
D1: SOD-323 Schottky
fet: PSMN0R9-25YLC (I tested this NXP fet before and it worked fine in another driver).
Thank you!
ps: I am also open to listen to other ideas, links to other boards and vendors. I have build an Oshpark board before and that all worked out.
Thanks, I was going to order a board with a bypass hole, if possible. But thank you for confirming that your board works (I assume you worked out all the issues you mentioned above?).
I would be happy to buy the Attiny25 but I don’t have the other missing parts (R3, R4 or C2 and the rest). Since I buy most of my parts directly from China it would take either too long or the item might get lost (happened before with my resistors).
Was hoping that someone has tested the V32 of the PCB (link: OSH Park ~ ) or whether it is comparable with the MTN 17DD?
Is there a reason why you want that particular version of this board? Earlier versions were very well-tested but I don’t think that one is.
The TexasAvenger board can be used with the “older” parts list, but it is limited by the firmware. Currently there’s only one solid FW that works with that board.
Richard at Mtn uses his own layout and parts on his newest designs
pilotdog68 - Since I am new to building drivers myself I thought the latest version would be the best. Apologies if that is not the case. I also checked the Oshpark projects @ BLF thread but I don’t know whether all drivers are in there (must be a ton of work to track all of that as well).
All I have is a hotplate to reflow solder the board, hence single-side only? I don’t know how to reflow a board with a hot plate / skillet and I can’t afford a SMD hot air rework station.
Can I leave the TexasAvenger driver empty on one side (the one with all the 7135 chips). I read a little bit through the details and wasn’t sure which channel goes to the FET and which one to the 1x7135.
my plan was to flash standard .hex files and not change anything (but I could try to do that too).
i have ordered the v32 board linked above and will report back after they have arrived. Unfortunately I also had to order a few parts - it will easily take 3-4 weeks to get everything and I’ll need to find time on a weekend to build/assemble. I don’t know how close this version is to the BLF 17DD driver but it is a Fet+1 I am after. haven’t ordered any FETs yet - not sure which one to go for… there are so many now.
Thank you, all. I will try to order and build it. worst thing that can happen is that I will be out of the money for the boards. But I am hopeful that they will work out.