Cold Brew – Custom Board design (59% complete!!!):

Notes (things done: striked through):

  • Delete the additional USB connector … No way I’m going to be able to SMT solder
  • Connect fan directly to 5V input … no need to stop fan … It runs quiet
  • Delete the diode that is attached to the fan
  • Need to use Analog (ADC1) inputs. Not ADC2 … something about wifi & ADC2 incompatible
  • Use ADC pins 36,37,38,39 only (low noise) for analog reading
  • Don’t use Serial Pins (RX & TX, GPIO1 & GPIO3)
  • Re-wire the H-bridge … 
    • The Enable should be set to same voltage as data (3.3V, not 5v)
    • Use all 6 logic inputs for more flexibility (1A, 2A, 3A, 4A, 1-2EN, 3-4EN)
    • Test this!
  • make fan feet shorter (so it compresses fan on heat sink 0.08in shorter)
  • Make feet a little fatter (so they don’t crack when torqued)
  • reorganize board so inputs are easier to play with
  • push board a tad more in so that drops are more lined up with light sensors (0.087in closer)
  • Program PWM thermal close loop
  • Solder components to new custom pcb
  • Order FDA approved food safe epoxy
  • Select new glass from Michaels
  • Buy 1/4″ glass cutter and install brass & copper components
  • Assemble the First “Hit Single” device and test


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