HX711 on-chip analog supply regulator, my mistake or datasheet mistake?
The comments on the SparkFun page for this product talk about this. To quote Member #461211:


  The formula for the output voltage AVDD appears wrong in the HX711
  datasheet and the SparkFun schematic. I think it should be VAVDD =
  VBG*(R1+R2)/R2 … not R1 in the denominator. My derivation and
  measurements support this. I had to dig into this to use VSUP = DVDD =
  3.3 V and change the 20 KΩ resistor to a 10 KΩ for a different load cell excitation voltage.


In short you are right, and not the first to observe this error. I encountered this myself not too long ago. Small world :).