Some of the connections didn't reflow well... (look at the bottom of the image). Maybe because the board was on standoffs to preserve the bottom side components ? I've never had this happen before.
Following steps :
- hot-air rework
- de-panelization (a bit harsh on the PCBs, I will have to rework the panel connections for the future revisions)
- through hole soldering
- heat sink fixed with thermal adhesive
As expected, v1.1 boards have better thermal performances (they are 4-layer instead of 2-layer). Heat spreads into the whole PCB including the mounting holes and I was able to pull a bit more current without the TMC5130 overtemp protection kicking in.
However these new boards still can't use the max 1.68A / phase current in this configuration. I will have to test with some fans that I have laying around if the full current can be achieved.
Anyway with the recent announcement of the TMC5160 by Trinamic a higher current Farfadet with external power stage will probably join the party :)
Next steps : soldering and trying the magnetic encoder and XLR extension boards... And a lot of software and documentation work !