Updated RFM12B-USB Interface

After review of the first RFM12B-USB interfacing, I noted that I'm driving the RFM12B over the design spec wrt the power supply. RFM12B is designed for 3.6V max VCC whereas USB supply typically is near 5V. As such, I've redesigned the interface to be 5V friendly with on-board 3.3V regulator and voltage dividers on the signal lines.

This board is double sided but does not need plated through holes as no top side soldering required on the components (except for vias). There is a technique on how to do that with Eagle which I may cover in next postings...