Agilent Technologies has introduced a fully integrated, optical-based analogue front-end (AFE) chip for narrowband powerline modems (PLMs) used in the energy utility and home networking markets. The chip replaces more than 30 discrete components, reducing board space by 50% and simplifying PLM design while improving system performance.
The Agilent HCPL-800J interfaces the PLM transceiver/ENDEC (encoder-decoder) IC with the AC powerline used as the signal transmission medium. It provides voltage and signal amplification, and galvanic isolation protects the user and the equipment being interfaced. It incorporates a control IC and a line IC, optically isolated from each other, and the modulated signal from the PLM transceiver is input to the control IC. This transmit signal is optically coupled to the line IC, then amplified and sent to the powerline. In the other direction, a potentially weak and noisy signal from the powerline is received by the line IC and optically coupled to the control IC, where it is amplified and output to the PLM transceiver.