Imagine you have a master controller device that control other devices in your house, and you don’t need to install any additional wires to facilitate the data communication between the master controller and the controlled devices. Yes you’s life will be easier since all you need is just plugging your devices into your power line outlet, the devices will communicate each-other through the power line while using the line to enpower them! The secret is the powerline modem, a modem that use the powerline wiring as their media to exchange the data. Philips Semiconductors has a single chip powerline modem solution, a TDA5051A IC chip. Here is the schematic diagram of this powerline modem circuit:

power line modem circuit circuit schematic

The TDA5051A single chip power line modem is equipped with protection of its output power stage and automatic gain control (AGC) of input signal. With simple coupling network, this power line modem is compliance with EN50065-1 power line communication standard.  This power line modem circuit uses ASK (amplitude shift keying) for the modulation, and operate on 5V supply. [Circuit’s schematic diagram source: Philips Semiconductors Application Notes]