@hotear I’ve tried the swap of R19 and R20 - it sort of works. Its REALLY difficult to hand solder 0603 parts!
I forgot that the temperature would invert so (it reads 50 degrees at room temperature and then goes down as temperature goes up).
For now I would recommend leaving the thermistor where it is and lowering the balance temperature.
If there is interest I can modify the module code to compensate for the inverted temperature if needed.
Might do but that link borked 
Looking good,
Can you explain how you made your programmer.
This is just an adaptor board for connecting a USBASP programmer to an ISP header using pogo pins.
A little bit of strip board, solder and wires.
Lots of lovely v4.3 boards arrived today (not publically available) - unfortunately they all have the swapped R19/R20 problem - doh!
Hi,
Long time follower, first time ‘potential’ buyer.
Which version is the best currently available for purchase as semi/fully-completed boards from JLPCB?
I was reading about 4.2, now I see 4.3 boards above, and on your Github you appear to have 5.15 … which version should I be looking at to order from JLPCB as completed boards? I want to minimize the amount of soldering I have to do myself.
Thanks!
4.21 is the one to go for. This can be assembled by jlcpcb for very little cost.
Have been following DIYBMS for a while now and ordered the 4.2 version through JLCPCB. I recieived a message from the engineers about polarity of some items, see below image.
In hindsight I should have cancelled the order and go with the 4.21 version, but the order is now assembled and shipped. I expect it to arrive in a few days.
What should I change to make it work?
What did the change? If you used the files from GitHub it would have been fine as it was.
You will have the R19/R20 problem mentioned in previous posts
I used the files from Github, so maybe it is fine
I can’t see any differences between the left and right board - can you ?
There is no difference, I am only not sure what the original should look like…
Looks very nice!
Actually looking at LCSC, they do have the ATTINY. But they don’t have the 2.0V shunt voltage reference. They do, however, have the 2.5 (LM4040BIM3-2.5/NOPB). If the circuit could be modified a bit to use this one, then all the parts would be available from LCSC.
The advantage of this is that, if the Kicad files are uploaded to EasyEDA, assembled boards could be ordered. They only charge for parts, assembly is free.
@stuart would you consider doing that? Perhaps the part could be switched with only software changes? Or perhaps use a voltage divider? I’m a software guy, I’m weak on hardware but it seems this could work, no?
Or, perhaps replace that part with a TLV431AFTA? Not a direct replacement but LCSC has this one as well.
I’ve already done an LCSC pre-assembled board - take a look at the 4.2 branch in github. This has all the parts (except the ATTINY) pre-assembled by JLCPCB (who use LCSC). No need to manually solder the tiny parts. The board version you want will be labelled 4.21
That’s great thanks! I’ll check it out. But why not the ATTINY?
Also, I don’t see a BOM in the 4.2 branch, is it the same as the master branch?
Is there no way for you to be able to load the board/parts as a standard build with LCSC that others could then use? Could make life easier. Does it run into the the ‘you can sell completed boards’ rules?
