Was studying the power supply part of the the EMON tx and for the 3.3 V in the schematic is see two parts one using the TOREX XC6206P332 called U$6 which will give 3.3v output, but there is a parallel circuit using the IC 7805 called IC2 which give 5V output. But in the actual PCB the IC2 does not seem to be there. What am i missing ?
Nothing. It has, as far as I know, never been used. The emonTx does have two regulators, one is used when power is from the 5 V d.c. supply or batteries, the other when power is taken from the a.c. adapter.
Yes IC2 is not populated and never has been. It was just an option in the early stages. I left the pads on the board since they are useful debug points to measure the supply voltage etc.
Thanks folks that clears up a lot of my confusion.