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AFE031: How to recover 120VAC, 50/60 Hz signal from FSK demodulation.

Part Number: AFE031

Hi,

In technical documentation of AFE031, 120VAC power line used for communication. but in this application if I want to recover the original 120VAC 50/60 hz signal in frequency shift keying method then how should I can do it?

I am deciding to use 50/60Hz signal as 'Space' frequency and 130Khz as 'Mark' frequency. on my slave control side i need 120VAC 50/60 Hz signal for other purpose. since we were taking that signal from FSK modulated line, how I shall recover it on slave side?

Any thought?

  • Hi Santosh,

    Multiple publications are available to provide background and guidance on the application of the AFE03x as the front-end transceiver in PLC/FSK applications, including:

    www.ti.com/.../sboa130a.pdf

    It is important to note, as you study the published report(s), that the AFE03x neither supplies power to the network nor derives power from the communications signals coupled to the host AC or DC power line.
  • Hi Neil,

    Thanks for your reply.

    In below picture, there are 3 controls out of which control 1 and 2 uses 120VAC power line for communication (highlighted in red). what I want, control 3 shall not disturb with modulated frequency and shall receive normal frequency i.e.50/60Hz. how should I achieve this?

  • Hi Santosh,

    I do not see the picture you are referring to..

    Please reattach or specify the document and figure number for reference.
  • In above picture, there are 3 controls out of which control 1 and 2 uses 120VAC power line for communication (highlighted in dotted line). what I want, control 3 shall not disturb with modulated frequency and shall receive normal frequency i.e.50/60Hz. how should I achieve this?
  • Hi Santosh,

    First of all, the MARK and SPACE carrier frequencies should be relatively close together in the same frequency band (e.g. CENELEC A). Then, for the network nodes that are communicating with each other (Control 1 and Control 2), follow the line coupling guidance provided in the application report. For the node(s) that do not require PLC (Control 3), simply apply a LC low-pass filter with cutoff frequency << the PLC carrier frequencies to the AC power line input.
  • Thanks Neil!

    One more question, The application note "sboa130a.pdf" is designed for 120VAC and 50/60Hz application, does same can be used for lower voltage application too (just like 24VAC), what schematic portion need to update or change for it?

    Thank you!

  • Hi Santosh,

    A lower voltage AC power line should not impact the PLC design significantly.

    Note, however, that the AFE031 requires 2 DC voltage inputs: 3.3VDC for logic and 7-24VDC for power amp.

    Will the Control Modules have separate DC supplies to power the AFE031 power amp and supporting circuitry?

    Or, will the DC voltages needed to power the AFE031 and supporting circuitry be derived from the 24VAC power line, e.g. with on-board AC-to-DC and DC-to-DC converters? If so, a filter inductor will be needed at the output of the 24VAC power supply and 24VAC input of each Control Module.