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April 2008 Rev 1 1/56
56
AN2744
Application note
ST7538Q power line FSK transceiver
dual channel reference design for AMR
Introduction
The ST7538Q dual channel reference design is a practical tool to start the activity of
designing an automatic meter reading (AMR) node based on the ST7538Q power line FSK
transceiver.
With this reference design, it is possible to evaluate the features of the ST7538Q and its
transmitting and receiving performances in an actual communication on the power line
network.
The ST7538Q reference design can be considered as composed of three main sections:
■ power supply section, specifically designed to coexist with power line communication and
to operate from a wide-range input mains voltage
■ modem and crystal oscillator section
■ dual channel line coupling interface section
The dual channel line coupling interface allows the ST7538Q FSK transceiver to transmit
and receive on the mains using two different carrier frequencies: 72 kHz and 86 kHz, both
within the frequency band A specified by the European CENELEC EN50065 standard for
AMR applications.
Figure 1. ST7538Q dual channel reference design board with outline dimensions
As it can be seen from the picture above, a special effort has been made to develop a
compact reference design board, oriented to practical applications.
Note: The information provided in this application note refers to the EVALST7538DUAL reference
design board.
56mm
98mm
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