3.3.3 PLC Coupling Circuitry Description

FCC 47 CFR Part 15.107 defines the 9-490 kHz frequency band for PLC in North America and Canada. The band from 148.5 to 490 kHz is not yet regulated in Europe.

Figure 3-8. FCC Frequency Bands

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

The PL460-EK board communicates in several band frequencies. The use of frequencies in these bands are restricted to consumer use, for example, for end-user applications such as industrial applications.

Microchip has designed several coupling reference designs for these band frequencies with variations in the BOM cost and the communication performance.

The PL460-EK board is assembled with a multiband design:

  • Main transmission branch

    • FCC

  • Auxiliary transmission branch

    • CENELEC A-Band

The FCC band design is assembled in the Main transmission branch and CENELEC A-Band in the Auxiliary transmission branch. The goal is to provide a cost-optimized fully-featured design according to the G3-PLC and PRIME requirements. Still, the PL460-EK board is designed to allow using other designs by changing the corresponding components and firmware configurations.

Table 3-8 summarizes all the configurations that can support the PL460.

In a multiband design, a configuration of the main transmission branch can be combined with any other of the auxiliary transmission branch.

Table 3-8. PL460 Coupling Configurations
Branch Configuration Name Description Frequency
 Band (kHz) PRIME
 Channel G3-PLC
 Band Applicable Regulation
Main CEN-A CENELEC A-Band 35-91 1 G3 CENELEC-A CENELEC EN50065
CEN-B CENELEC B-Band 95-125 — G3 CENELEC-B CENELEC EN50065
FCC FCC Band 151-472 3,4,5,6,7,8 G3 FCC CFR Title 47 Part 15 Subpart B
FCC High-attenuation FCC Band 151-472 3,4,5,6,7,8 G3 FCC CFR Title 47 Part 15 Subpart B
Multiband Single-branch FCC & CEN-A FCC & CENELEC A-Bands 35-91, 157-472 1,3,4,5,6,7,8 G3 CENELEC-A & G3 FCC CENELEC EN50065, CFR Title 47 Part 15 Subpart B
Auxiliary CEN-A CENELEC A-Band 35-91 1 G3 CENELEC-A CENELEC EN50065
CEN-B CENELEC B-Band 95-125 — G3 CENELEC-B CENELEC EN50065
Important: Check the online resources from the Microchip website to download the proper files according to your desired design.
The PLC coupling circuit is composed of three sub-circuits:
  1. Transmission Stage
    1. Main transmission branch, which makes use of the embedded PLC driver
    2. Auxiliary transmission branch, used for multiband designs
  2. Reception Stage
  3. Coupling Stage

The following sections describe the purpose of every sub-circuit assembled in the PL460-EK board.