Power Line Communication (PLC) is a communication technology that enables sending data over existing power cables. This means that, with just power cables running to an electronic device (for example) one can both power it up and at the same time control/retrieve data from it in a half-duplex manner.
For the purpose of understanding, PLC can be broadly viewed as:
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Narrowband PLC - works at lower frequencies, lower data rates, and has longer range (up to several kilometers), which can be extended using repeaters.
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Broadband PLC - works at higher frequencies, high data rates and is used in shorter-range applications.
PSoC 1 PLC Solution works at 132 kHz and at 2400bps. This comes under Narrowband PLC.
There is another way to classify Power Line Communication.
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PLC over AC lines - Main focus of most companies.
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PLC over DC lines - distributed energy generation, and PLC in transportation (electronic controls in airplanes, automobiles and trains).
PSoC 1 PLC solutions supports both PLC over AC and DC lines for different range of voltages.
PLC is like any other communication technology whereby a sender modulates the data to be sent, injects it onto medium, and the receiver de-modulates the data to read it. The major difference is that PLC does not need extra cabling, it re-uses existing wiring.
Cypress offers single chip PLC solutions which is essentially an optimized System-on-Chip (SoC) solution, which includes the complete PLC - MAC and PHY. Cypress offers ready-to-use Physical and Network layer, and a user-programmable application layer. The CY8CPLC20 device combines the FSK modem and network protocol with the Cypress PSoC® core. The PSoC contains a 24-MHz CPU with configurable digital and analog blocks. With its unique array of configurable blocks, PSoC1 is a true system level solution providing MCU, memory, analog, and digital peripheral functions in a single chip. CY8CPLC10 does not integrate PSoC1 core and hence needs external host PSoC1 for communication.
The Cypress PLC solution enables secure and reliable communication over Powerline. Cypress PLC features that enable robust communication over Powerline include:
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Integrated Powerline PHY modem with optimized filters and amplifiers to work with lossy high voltage and low voltage Powerlines.
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Powerline optimized Network Protocol that supports bidirectional communication with acknowledgement based signaling. In case of data packet loss due to noise on the Powerline, the transmitter has the capability to retransmit the data.
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The Powerline Network Protocol also supports 8-bit CRC for error detection and data packet retransmission.
A Carrier Sense Multiple Access (CSMA) scheme is built into the Network Protocol; it minimizes collision between packet transmissions on the Powerline, supports multiple masters, and enables reliable communication on a bigger network. To interface a PLC device to the Powerline, a coupling circuit is required.