Accurate analog signal control is the key to the safety of factory equipment and continuous operation of machines.
The Internet of Things, or IoT, is a fairly broad term, and it can be subdivided into smart city, smart transportation, smart healthcare and Industrial Internet of Things (IIoT) in terms of applications.
Speaking of IIoT, there is a highly correlated concept of Industry 4.0, which refers to a new phase in the Industrial Revolution that focuses heavily on interconnectivity, automation, machine learning and real-time data. In addition to being used in consumer applications, the IIoT is also widely promoted to enable intelligent industrial operations based on the IoT.
Supported by IIoT, factory automation can improve production efficiency, realize stable product and solve the labor shortage. Today, the rapid development of technology has accelerated production line automation, realized unmanned vehicle delivery system and promoted the use of robots and manipulator arms. However, it is still challenging to build a real smart factory. Before digital transformation, traditional factories usually have front-line workers to record production status, make the required forms and collate relevant data, and managers often make decisions based on their experience and assumptions. This kind of working process may take a lot of time to organize reports and wait for managers to make decisions, thus delaying the time to troubleshoot.
The primary step of upgrading a traditional factory to a smart factory is to connect the old devices to a programmable logic controller (PLC) and a sensor, perform data acquisition by the sensor front end and data analysis by visualization device, and then transfer the data to PLC for real-time monitoring through communication devices, and finally sent back to the cloud for management, thus forming a complete industrial networking.
To implement such a technology, embedded or non-embedded networking devices must be assembled in the existing devices. Featured with high processing speed, small size and low cost, MCUs are used to perform functions such as communication, edge computing, real-time response and motor control of hardware devices, thus to promote the transformation of traditional factories.
IIoT features flexible and high-speed communication networks, fast distributed computing capabilities and edge computing technique that helps improve analysis. These technologies and capabilities are indispensable. In addition, the PLC for signal capture and drive control and the motor control system assisting factory equipment operation have an increasing requirement on system processing capability. Traditional 8-bit MCUs can no longer meet the requirements of manufacturers, and 32-bit MCUs are recommended to achieve better performance (Figure1).
Figure 1: Import IIoT device with AT32 MCU
Arm processor cores are currently the industry standard for highly integrated and low-cost MCUs used in industrial and automotive systems. In particular, the ARM Cortex-M4 32-bit MCU inherits advantages of Cortex-M3 and also embeds a digital signal processor (DSP) and optional single-precision floating point unit (FPU). Therefore, Cortex-M4 has high-precision and complex computing capability and accessibility, which makes easy for developers to write firmware.
Cortex-M4 32-bit MCU can effectively improve low latency, accuracy and power management. It simplifies and integrates traditional MCU functions into a single chip, features large memory and flexible application, optimizes system cost and facilitates engineers to develop through software development platform, supporting high performance, real-time control, communication network, data analysis and security control. Therefore, based on ARM Cortex-M4/M0+ 32-bit MCU, ARTERY Technology launched the AT32 MCU series and achieved technical breakthroughs in computing efficiency and precision, making the AT32 MCU series superior to chips of the same level on the market. Here are advantages of the AT32 MCU series in industrial automation.
Real-time response and control
Accurate analog signal control is the key to the safety of factory equipment and continuous operation of machines. It is critical to control the signal within the specified period and process mass data rapidly to perform real-time response and control. In particularly, a motor with a speed of up to hundreds of thousands rpm has high current frequency and low motor coil inductance; therefore, high-frequency and high-resolution PWM voltage is required to enable the motor to run efficiently and stably. The AT32F435/437 series developed by ARTERY Technology features 288 MHz maximum frequency, supports floating point unit (FPU) and embeds 4032 KB Flash and 512 KB SRAM to enable CPU to perform zero-wait-state read and write access (Figure 2). In addition, the AT32F435/437 series also embeds automatic clock calibration (ACC) block that can be used to calibrate the internal 48 MHz clock (HICK) to ensure the best accuracy of HICK within the chip operating temperature range and meet the requirements of various motion control and intelligent control for high-speed computing and high precision.
Figure 2: Zero Wait-state Flash Mapping Area
Simplified design to reduce system complexity
The AT32 MCU integrates peripherals such as CAN bus, UART, SPI/I2S, ADC and multi-purpose timers into a single-chip system that is optimized through high-level software programming and built on a flexible hardware block. The software is set according to actual application requirements, and it is extendible and compatible with the system, making the system less complex. In addition to these interfaces, the AT32 MCU also has dual DMA controllers and is compatible with IEEE-802.3 10/100Mbps Ethernet and USB OTG to improve data transmission efficiency and reliability. Furthermore, a complete system ecological chain has been established, which includes the development environment, real-time operating system (RTOS) and third-party software resources verified by ARTERY Technology, and complies with the IEC-60730 international safety standard specification formulated by the International Electrotechnical Commission (IEC). Such rich resources and supports help rapid development and launching of products to the market.
Large-capacity memory to improve flexibility
The AT32 MCU can be used with standard expansion board and built-in debug interface for flash programming and run control. The quad SPI Flash (QSPI) interface has high bandwidth for read, which can accelerate the data access and editing of high-performance embedded system and complete system rapid programming. Based on advanced technology, AT32 MCU integrates large-capacity SRAM for data caching, which can realize more complex system code and application flexibility. The AT32F403A/407 series and AT32F435/437 series provide optional 256~4032 KB Flash and 96~512kB SRAM, and are flexibly used for various industrial automation control, such as mechanical equipment for chemical industry, plastic production, textile manufacturing, packaging and printing, as well as central air conditioner and environmental protection equipment (Figure 3).
Figure 3: AT32 M4/M0+ MCU FAMILY
Improve energy efficiency
In the future, more control programs and industrial sensors will be used in industrial equipment to enhance security, all of which require powerful computing capabilities. For example, the anomaly detection function will be added to industrial equipment to remind operators to repair the equipment before it breaks down and ensure safety operations in case of equipment failure, to reduce the downtime and provide more communication methods.
In the upgrade of factory automation, low-power electromagnetic flow meters and ammeters will be used to realize wireless meter reading and data transmission, thus, to save human resources and improve efficiency. The AT32WB415 series uses low-power Bluetooth 5.0 (BLE) and wireless communication MCUs that integrate functions of Bluetooth RF receiver/transmitter and baseband; therefore, it is the first choice for factory equipment configuration. As factory equipment needs to be connected to network at all times, energy management is a major challenge, and it is necessary to achieve low operating and standby power consumptions. ARTERY Technology plans to launch the AT32L021 series in the second half of 2022. The AT32L021 series features a maximum frequency of 72MHz, rich on-chip peripherals, one extended 12-bit ADC with sampling frequency up to 2Msps, and I/O interfaces that are almost 5V-tolerant, and it is suitable for high-speed data acquisition, industrial control and motor control. In addition, the chip has low power consumption of about 1μA in Standby mode and about 20μA in Deepsleep mode.
Market Research Future expects that the IoT MCU market share is expected to grow at a compound annual growth rate (CAGR) of 12% from this year to 2023, when the annual revenue will reach nearly $4 billion. The IIoT applications are more focused on the connection of factory equipment to mass remote sensors, so MCUs need to meet the requirements of high-speed data transmission and processing at low power consumption, which is also the goal that ARTERY Technology has been striving to achieve.