3.3.5 PLC Coupling Circuitry Description

The European regulations concerning Power Line Communications are described in CENELEC standard EN 50065. This standard applies to electrical equipment using signals in the frequency range 3 kHz to 148,5 kHz to transmit information on low voltage electrical systems, either on the public supply system or within installations in consumers' premises. The following figure shows the different frequency bands allocated to the different applications.

Figure 3-9. CENELEC Frequency Bands

FCC section 15 defined 10-490 kHz frequency band for PLC in North America and Canada. The FCC band (10-490 kHz), is not yet regulated in Europe.

PLC COUP011 is designed to communicate in FCC band, from 151 to 471 kHz.

Figure 3-10. FCC Frequency Bands

The PL360G55CF-EK evaluation board communicates in the CENELEC A-Band and FCC Band frequencies. The use of frequencies in these bands shall be restricted to consumer use; for example, for end-user applications such as industrial applications.

Microchip has designed four coupling reference designs for this frequency range with variations in the BOM cost and the communication performance. Table 3-12 summarizes the main features of the available designs.

Table 3-12. Characteristics of PLCOUPxxx Boards for CENELEC A-Band and FCC Band
Board Name Description Frequency
 Band (kHz) Branch Electrical
 Isolation PRIME
 Channel G3-PLC
 Band Applicable Regulation
PLCOUP007-ISO G3-PLC CENELEC A & PRIME Channel 1 compliant 35 - 91 Single Yes 1 G3 CENELEC A CENELEC EN 50065
PLCOUP008-NONISO

Non-Isolated

G3-PLC CENELEC A & PRIME Channel 1 compliant 		35 - 91 Single No 1 G3 CENELEC A CENELEC EN 50065
PLCOUP011-ISO Dual PRIME / G3 for CENELEC A and FCC bands

35 - 91

151-472

 Double Yes 1, 3, 4, 5, 6, 7 and 8 G3 CENELEC A and FCC CENELEC EN 50065
PLCOUP011-NONISO

Non-Isolated

Dual PRIME / G3 for CENELEC A and FCC bands

35 - 91

151-472

 Double No 1, 3, 4, 5, 6, 7 and 8 G3 CENELEC A and FCC CENELEC EN 50065

The PL360G55CF-EK board is assembled with the PLCOUP011-ISO coupling design. The goal is to provide a cost-optimized fully-featured design according to the G3-PLC and PRIME requirements. Still, the PL360G55CF-EK board is designed to allow using all the other coupling designs by changing the corresponding components and firmware configurations.

Important: Check the online resources from the Microchip website to download the proper files according to your desired CENELEC A-Band and FCC Band design.
The following figure shows the PLC Coupling assembled (PLCOUP011-ISO) which is composed of four sub-circuits:
  1. Transmission Stage
    1. Transmission Stage for CENELEC A-Band
    2. Transmission Stage for FCC Band
  2. Filtering Stage
    1. Filtering Stage for CENELEC A-Band
    2. Filtering Stage for FCC Band
  3. Coupling Stage
  4. Reception Stage
Figure 3-11. PLC Coupling Schematic on PL360G55CF-EK Board
Remember: PLC Coupling circuitry includes two yellow LEDs, D104 and D110, for visual indication of PLC frames transmission through the corresponding branch.

The following sections describe the purpose of every sub-circuit assembled in the PL360G55CF-EK board.