skyjumper:
Which is the proper choice for serial? It seems that the TXB series needs the device to source 2mA to drive it, but the TXS does not.
Well, there are at least two ways to find out... post at TI or Adafruit (their forums are pretty good) or buy the Adafruit txb breakout and just try it out. My guess is that the txb would work.