MCU: Key factor in minimizing power loss

As the worldwide consumption of power increases exponentially, companies are being pushed to develop products that help reduce power footprint. Providing insights into the role of microcontrollers in improving system power efficiency, ECN Asia spoke with Andy Wong, Senior Manager for MCU in Industrial Applications, Infineon Technologies. Excerpts:

Energy conservation is expected to show sizeable growth in its use of MCUs. How can Infineon’s MCUs help in system power efficiency?

Infineon provides a total solution to the industrial market, including low-resistance MOSFETs, IGBTs, power modules and microcontrollers for real-time embedded control. With its application kits, Infineon provides advance control algorithms like filed oriented control (FOC) for applications like home appliances, solar inverters and industrial motor drives. We help customers adapt to new technologies in the shortest time. One example is the market for airconditioning systems. Using an inverter base system will reduce the overall power consumption by up to 30 percent. Infineon’s DAvE Drive autocode generator for motor control helps engineers develop software with a few mouse clicks.

What are the challenges in designing products to meet this trend?

Firstly, the continuous price reduction of microcontrollers enables the current and emerging industrial devices to be used in cost-sensitive applications.

Secondly, the pure arithmetic performance of a core is insufficient measure for the efficiency of a microcontroller in a system, hence the architecture and on-chip periphery should be considered.

Thirdly, in order to tackle applications like electrification of pumps, etc., it is inevitable that the focus is on reducing development costs for the customers. These points are very important for the wide range of industrial customers who often have to deal with very small project teams and budget. The challenge is to develop products that are cheaper, better, and simpler.

‘Cheaper’ means to optimize cost on system level where the customers can optimize their bill of materials. By using Infineon microcontrollers, it is possible to use one microcontroller instead of two because of its real-time performance and rich feature sets. We offer the performance of 16-bit in our 8-bit family called XC800, and 32-bit class microcontrollers in our 16-bit XE166 family. Another example is the realization of a smart supply concept that keeps the microcontroller as simple and as cheap as possible.

‘Better’ means that the microcontrollers’ real-time performance needs to adapt to the steadily improving control algorithms like FOC. Here, the entire microcontroller architecture counts. Infineon provides real-time performance with autonomous operating PWM unit hardware coupled to the ADC. Furthermore, calculation power for controls like FOC is realized by co-processing units, like Infineon’s vector computer on its XC800 family or an integrated MAC-unit handling DSP feature in the XE166 family.

‘Simpler’ is achieved by providing developers with the right toolset such as reference designs for fast time-to-market. Infineon has established its application kits very well for this purpose to offer turnkey solutions with reference hardware design and software code. Man months of software and hardware development can be saved by using the DAvE Drive or Dual Motor Control Kit.

What are the other business trends in the MCU industrial segment?

The industrial segment is moving into a new era where the focus is conserving the world's energy resources. Industrial applications like solar inverter, wind power energy converter, LED and HID lighting are emerging. The industrial segment is focusing more on complex control to improve energy efficiency. Microcontrollers are becoming more important as they provide the right functionality and performance for control algorithms and further improve safety and reliability of the system. Improvement of energy efficiency in industrial products means minimizing power losses. This requires intelligent and precision control. Infineon is focused on providing efficiency improvements in industrial applications with its comprehensive portfolio of microcontrollers for real-time embedded control.

What are the main factors behind the growing trend for 32-bit MCU designs in markets once dominated by 16- and even 8-bit chips?

The 32-bit architectures are growing to satisfy the performance needs of tomorrow’s applications, as many suppliers need to increase the core performance in order to do so. But the core is not the dominating part of the microcontroller performance. Real-time capabilities and architectures that solve the application's demand very efficiently are key factors in selecting the microcontroller. The price for the overall performance is also an important criterion in embedded control solutions.

Strong growth is expected for 32-bit microcontrollers. Does this mean demand for 8- and 16-bit models will decline?

Since about 10 years ago, analysts are predicting that 16- and 32-bit microcontrollers will displace 8-bit in the market. But as we all know, the 8-bit segment continues to bring the right performance for very price-sensitive markets. The average selling price of 8-bit MCUs continues to go down with performance increasing significantly. Infineon’s XC800 family is one example. Eight-bit microcontrollers will stay.

Do multi-core processor architectures have any relevance to the microcontroller market?

Multi-core architectures are not new in the embedded world. Infineon first introduced its cutting-edge 32-bit real-time microcontrollers with TriCore ─ a core which combines real-time capabilities of microcontrollers, computational power of DSPs, and the price/performance benefits of RISC load-store architectures ─ 10 years ago. In the TC11 families for industrial applications, a peripheral control processor (PCP) handles all the peripheral tasks to offload the main CPU. This architecture provides a good platform for function safety implementations in industrial applications.