Microcontrollers are mini computers-on-a-chip that enable smart interactivity for products and machines. With broad applications from smart home gadgets to industrial automation equipment, demand for advanced yet affordable microcontrollers continues to grow rapidly.
New use cases like AI on the Edge are also expanding the capabilities expected from modern "MCUs". This article looks at 5 of the most versatile, cutting-edge and easy-to-prototyper controllers available today. We‘ll explore the key architecture, specs, and real-world applications of each to help identify which is best suited for your next project.
Powerful Processing for Industry: STM32 Cortex-M4F
STM32 series microcontrollers offer high performance 32-bit Arm Cortex-M cores clocked up to hundreds of MHz to provide plenty of horsepower for data-intensive applications like motor control, sensors fusion, edge analytics and more.
With sophisticated peripherals like floating point units integrated alongside rich connectivity options like Ethernet, USB and CAN bus, STM32 chips are designed for more heavy duty applications in automation, robotics, industrial equipment and other complex machines.
Example products powered by STM32 processors include drones, 3D printers, medical devices, building control systems and more. Their versatility across voltage ranges plus RTOS support have made them an industry workhorse.
Key STM32 Specs:
- 32-bit ARM Cortex-M4F core @ 100MHz+
- Up to 2MB Flash, 320KB RAM
- Floating point unit
- Crypto/security accelerators
- Advanced motor control PWM
- Rich analog/digital peripherals
- Industrial temperature rating
- As low as $3 in volume
WiFi/BT for IoT: Espressif ESP32 SoC
Purpose built for connected devices, the ESP32 packs WiFi, Bluetooth, hundreds of MHz of processing power and advanced features like OTA updating into an incredibly compact, low cost and low power system-on-a-chip.
With both single and dual core options plus a huge range of memory configurations up to 16MB Flash, the ESP32 readily powers everything from sensors and wearables to home automation devices, industrial equipment, mesh networks and more.
By handling wireless connectivity plus the application processing in a single unified chip, the ESP32 allows rapid development of sophisticated IoT devices. The wide operating voltage and industrial temperature rating also allow flexible implementation across a vast array of product types.
Key ESP32 Specs:
- 240 MHz dual core Tensilica LX6 CPU
- Up to 18x ADC channels, capacitive touch
- WiFi 802.11b/g/n (2.4 GHz only)
- Bluetooth v4.2 BR/EDR and BLE
- Crypto hardware acceleration
- RTOS and TCP/IP stack support
- QFN / module form factors
- As low as $2.50 in volume
Arduino Compatible Power: RP2040 Microcontroller
Designed by Raspberry Pi, the dual-core RP2040 delivers surprising punch in a tiny footprint and minimal cost. It features 133MHz Arm Cortex M0+ processors that deliver up to 10x the performance of old staples like the ATmega328P in Arduino Uno boards.
With extensive I/O options from GPIO to UARTs, I2C, SPI etc combined with a huge 264KB internal SRAM, the RP20440 readily powers a new generation of capable yet affordable microcontroller boards and embedded products. Use cases range from robotics and instrumentation to home automation, IoT devices and much more.
The tiny DIP form factor, multiple oscillator options plus broad 3.3V power supply range make integrating the RP2040 very straight forward. With easy Arduino and Raspberry Pi compatibility, it offers a frictionless upgrade path to create far more capable devices compared to older 8-bit alternatives.
Key RP2040 Microcontroller Specs:
- Dual core Arm Cortex M0+ @ 133 MHz
- 264KB internal SRAM
- Support for external quad SPI Flash and SRAM
- 30 GPIO pins, 3 analog inputs
- Multiple oscillators incl. crystal
- USB 1.1 controller and PHY
- As low as $1 in volume
Feature Packed & Low Cost – ATmega 328P MCU
As the microcontroller used on popular boards like Arduino Uno, the ATmega328P offers a well proven, remarkably Low cost yet surprisingly capable 8-bit option.
With 32KB Flash and a 16MHz crystal oscillator, the ATmega328P can readily run your compiled C/C++ code. Priority interrupts, multiple sleep modes down to sub-uA plus built-in EEPROM make it versatile for low power applications like sensor devices.
The availability of mass produced, compact Arduino module boards has fueled adoption, particularly for prototyping. Quests to create smaller, cheaper yet more capable Arduino-compatible boards continues to improve price/performance.
Example DIY and commercial products powered by ATmega328P or similar MCUs include everything from simple robotics and IoT sensors through to complex CNC machines, 3D printers, quadcopters, weather stations and smart home tech so despite its age, the ATmega328P remains a nimble workhorse.
Key ATmega 328P Microcontroller Specs:
- 8-bit AVR RISC @ 16 MHz
- 32KB Flash, 2KB SRAM, 1KB EEPROM
- 20 GPIO pins
- Multiple oscillator options
- Multiple sleep modes down to 0.2uA
- As low as $1.20 in volume
Minimalist 8-bit Option: ATTiny MCU Family
Where ultra compact size and basic functionality is required, the ATTiny family offers a tidy low cost, low power microcontroller option. With 8-20 pin DIP through surface mount options available, ATTiny chips work well when integrated into space constrained products.
With tiny amounts of code and RAM space compared to other entries in this round-up plus processing grunt more akin to 1990’s calculators, ATTiny MCUs are less flexible but readily handle switching, timing, sampling, pulse measurement and other straight forward interactions.
Example uses include simple robotics, LED displays/lighting, switch/sensor modules, motor drivers, hand held devices, clock modules and more. The minimal silicon makes them economical for high volume products.
While less broadly capable than the other microcontrollers featured here, the ATTiny family fills a niche where an uncomplicated, dedicated low cost chip is ideal.
Key ATTiny85 Microcontroller Specs:
- 8-bit AVR @ up to 20MHz
- 8kB Flash, 0.5kB RAM
- Up to 8 GPIO
- Multiple oscillators incl. internal
- Multiple sleep down to 0.5uA idle
- As low as $0.25 in volume
Comparing Key Specs
| Microcontroller | Core / Word Size | Speed MHz | Flash KB | SRAM KB | GPIO Pins | ADC | Hardware Acceleration |
|---|---|---|---|---|---|---|---|
| STM32F407VG | Arm Cortex-M4 32-bit | 168 | 1024 | 192 | 114 | 12bit 3MSPS | Floating Point, DSP, Crypto |
| ESP32-S2 | Xtensa LX7 32-bit | 240 | 320 | 320 | 43 | 18bit 8MSPS | WiFi/BT, AES, SHA |
| RP2040 | Dual Arm M0+ 32-bit | 133 | — | 264 | 30 | 12bit 1MSPS | — |
| ATmega328P | 8-bit AVR | 16 | 32 | 2 | 23 | 10bit 100kSPS | — |
| ATTiny85 | 8-bit AVR | 10 | 8 | 0.5 | 6 | — | — |
Conclusion
This overview just touches the key points of a few popular microcontrollers that offer great versatility and value. Additional options from manufacturers like Microchip, NXP, Renesas and others also offer compelling alternative MCU choices.
Factors like processing requirements, memory needs, operating voltages, pins, packaging and peripherals like ADC/DACs, networking, motor control, crypto hardware and more help determine the best fit for your specific project needs from the thousands of microcontroller variants available.
With microcontrollers becoming more capable while retaining low cost and minimal power draw, they will continue proliferating as key components enabling intelligent interactions across consumer and industrial electronics alike.