The STEVAL-PLC001V1 evaluation board targets compact programmable logic controller (PLC) applications in the factory automation domain. It features a powerful human machine interface (HMI) thanks to the 3.5” TFT touchscreen mounted on the PCB, which eases interaction with the tool.
The board implements a galvanically isolated PLC control unit with robust digital input, digital output modules, expansion connectivity options, and interfaces.
The control unit consists of a powerful 144-pin STM32F746ZGT7 MCU, which handles the industrial IOs on one side and the TouchGFX display technology on the other side, implementing the ladder logic programming code and several additional options.
Highly robust and reliable industrial digital input and output modules are placed symmetrically on the PCB, making the system a 12+12 PLC, that is, a PLC GUI optimized for STM32 microcontrollers, which manages 12 industrial inputs and 12 industrial outputs.
The 12 industrial inputs have been implemented through the combination of an eight-channel CLT01-38SQ7 and two dual channel CLT03-2Q3 ICs.
The CLT01-38SQ7 features 6.25 MHz SPI with daisy chain capability to connect, in this case, the eight-channel output ISO8200AQ and reverse polarity, whereas the CLT03-2Q3 features two high- and low-side compatible independent channels, which can be powered from the external sensors they interface with, and the capability of running in the 60 V range for fail-safe applications.
The 12 industrial output array consists of an eight-channel ISO8200AQ IC and a four-channel IPS4260L low-side intelligent power switch.
The ISO8200AQ offers a daisy-chain SPI interface and embedded galvanic insulation, separating logic and power side of 4 kV and making the solution cost-effective (no opto-coupler is needed).
The STEVAL-PLC001V1 also features connectivity options typical of commercial PLCs through the morpho connectors mounted on the PCB bottom, ensuring compatibility with STM32 Nucleo expansion boards.
The embedded ICs for industrial IO management allow great flexibility in terms of technical features, protections and embedded diagnostics, when interfacing industrial range inputs (that is, sensors and valves) and outputs (that is, lamps, alarms, and actuators) with the logic side.
The STSW-PLC001 companion software package, freely available on www.st.com, allows experimenting with these advanced features and their combination.
Thanks to this software and the smart user interface offered by the TouchGFX, you can learn how the ICs work and exploit ready-to-use examples as well as ladder logic demonstrations and projects.