Bench Talk

How to Select the Best MCU for Long-Life and Energy-Efficient Processing

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The global microcontroller unit (MCU) market is experiencing substantial growth. Grandview Research estimated the market to be $17.9 billion (USD) in 2020 and expand at a CAGR of 10.1 percent from 2021−2028. Increased demand for embedded control systems in multifunctional devices, as well as a focus on sustainable energy management, play a key role in the growth of the market.

Because of the predicted growth and the fact that MCUs are simple to program, an increased number of competitors are entering the market. This trend has constrained unit prices, lifting demand. The MCU manufacturers in the industry are focused on developing innovative designs that support wireless sensing, connectivity, and automation. There are various types of MCUs, each of which is more suitable for some applications over others. Understanding the types of MCUs and typical applications will outline how to select the best MCU for the use case.

Type of MCUs

All microcontrollers share the ease of programming, efficient footprint, and integration-friendly design style. But the significant types of MCUs have slightly different nuances, making some better suited for a given application than another:

• PIC (peripheral interface [micro]controller): Based on RISC ISA, PIC offers ease of programming and speed.
• 8051 (system on a chip): Based on Von Neumann architecture, 8051 is an 8-bit MCU chosen for energy management, touch-sensing capability, automotive, and medical devices.
• AVR (advanced virtual RISC):  Based on RISC ISA and modified Harvard architecture, AVR is the low-cost choice while maintaining its effectiveness.
• MSP (mixed-signal) – Based on some features of RISC and Von-Neumann architecture. MSP MCUs are known for their ultra-low power consumption.

Applications and Key Features of MCUs

Engineers use microcontrollers in devices for a wide array of applications, including smart devices and wearables. These application areas need to offer a high degree of consumer controllability. The use cases must integrate with the controller by the Internet of Things (IoT), asset tracking and RTLS, or consumer medical devices to achieve the desired level of control. These areas require an easy-to-integrate, compact controller solution to provide their users optimal control and performance during use.

In addition, MCUs have a prominent place in enabling Industry 4.0. They offer a compact, long-life, energy-efficient option for data processing. The small footprint makes them ideal for embedding within devices and integrating into final products.

MCU Features Dictate Selection

Industry-leading MCU technology has a wireless connectivity function and maximizes its performance-to-power ratio for the IoT. While sharing the traditional needs delivered by all MCUs, the applications described above each have one or more success-determining performance features that dictate the appropriate MCU choice. In mobile devices, a small-form factor may be the driving engineering need. For smart devices, extended battery life may be the critical feature. When it comes to medical device applications, technical robustness and integration opportunities might determine the selection of an MCU. These use cases provide an opportunity for an advantaged product solution.

Product Focus: MAX32655

An advanced system on a chip (SoC) MCU, the MAX32655 Low-Power Wireless Microcontroller by Maxim Integrated efficiently handles the computation of complex functions and algorithms, such as the data coming from medical devices. The processor is used in applications such as asset tracking; hearables; fitness, health, and medical wearables; industrial sensors; and wireless computer peripherals with I/O devices.

The MAX32655 addresses the common design challenges of battery life, Bluetooth^® Low Energy direction finding, and comes in a small compact envelope while delivering the performance customers and users expect. The MAX32655 offers high reliability, low power, and current Bluetooth Low Energy features that users value in an MCU. It is an especially ideal choice for IoT as well as smart wearable and medical devices applications with power/lifetime challenges and the need to have seamless integration with unquestioned reliability and low complexity.

The MAX32655 outpaces the market with feature offerings like ECC and a dedicated RISC V BLE processor. Its sizeable onboard memory of 512KB flash and 128KB SRAM is significant for high-data medical device applications. It accepts many high-speed interfaces to enable the rapid transfer of data. The MAX32655 is a power system on a chip choice for low-cost, high-performance, energy-efficient processing. It offers the features engineers look for when evaluating MCUs.

Maxim Integrated offers the MAX32655 Evaluation Kit as a development platform for the MAX32655 Low-Power Wireless Microcontroller. The kit comes with an easy-to-use 320 x 240 color TFT resistive touch display for ease-of-use. A MAX32625PICO Debugger, JTAG Debugger, and all required cables are also included. This evaluation kit comes with a pre-loaded demo that can be accessed using the ARMCortexToolchain.

Selecting the right MCU is essential, as not all components are created equal for a given application. But, knowing your critical-performance parameters and those that are only nice to have helps you know which MCU is ideal for your application.