I am looking for a simple way to encode some data over a dc power line. (Probably using a very low cost IC) In my design, I have a port that provides 5V, 200mA for connecting some device, but now I like to extend the capability of my port to send and receive some data over that port. The idea I have is to encode data over 5V line. The distance the signal needs to travel is in the order of 10-15cm. Never more than this.
I have no data rate requirement but If I could achieve a 1-2Mbps it would be fantastic. If this is not possible, I am OK with a lower transmission rate. This would be a closed loop system, i.e. I control both ends. Therefore, I don't need to worry about standards etc.