Technical Comparison Report: ESP32 vs. Teensy 4 Series

Overview

The ESP32 series, developed by Espressif Systems, and the Teensy 4 series, created by PJRC, are both highly capable microcontroller development platforms. ESP32 is well known for its integrated wireless capabilities, while the Teensy 4 series is recognized for its raw processing power and real-time performance.

Processing Power

The ESP32 series features dual-core Xtensa LX6, LX7, or single-core RISC-V processors, depending on the model. These typically operate up to 240 MHz. In contrast, the Teensy 4 series, including the 4.0 and 4.1 models, use an ARM Cortex-M7 processor running at 600 MHz. Teensy boards also include support for both single and double-precision floating point operations, while ESP32 generally supports only limited or single-precision FPU.

RAM and flash memory also differ significantly. ESP32 devices offer around 520 KB of internal SRAM and 4 MB to 16 MB of external SPI flash. Teensy 4.0 includes 1 MB RAM and 2 MB flash, while the 4.1 expands to 8 MB flash and supports 8 MB of external PSRAM.

Connectivity

ESP32 is equipped with integrated 802.11 b/g/n Wi-Fi and Bluetooth (including BLE). Some variants, like the ESP32-S3, also support Ethernet via external PHY. USB 2.0 OTG support is available on newer models. Contrary to some misconceptions, ESP32 also supports CAN (Controller Area Network), although implementation may vary by model and may require external transceivers.

Teensy 4 boards lack built-in Wi-Fi and Bluetooth but do offer USB 2.0 (host and device), and the Teensy 4.1 can be connected to Ethernet via an optional adapter. Teensy 4.0 and 4.1 also include a CAN controller, which makes them suitable for automotive and industrial applications.

I/O and Peripherals

ESP32 boards offer around 34 GPIO pins, up to 18 12-bit ADC channels, two 8-bit DAC channels, and approximately 16 to 20 PWM channels. They support multiple SPI, I2C, and UART interfaces. Teensy 4 boards provide a larger number of GPIOs (40 on the 4.0 and over 55 on the 4.1), two 12-bit ADCs, up to 31 PWM channels, and extensive UART support.

Teensy 4.1 also includes a built-in microSD slot and additional memory expansion capabilities. While ESP32 supports SD cards via SPI or SDIO, it generally requires additional components.

Power Consumption

The ESP32 series includes several power-saving modes such as light sleep, deep sleep, and a unique ultra-low-power (ULP) coprocessor. These features make it highly suitable for battery-powered IoT applications. In contrast, while the Teensy 4 series is energy-efficient for its performance class, it does not offer the same level of ultra-low power modes and is less ideal for long-term battery operation.

Development Ecosystem

ESP32 benefits from broad support in Arduino IDE, PlatformIO, and its official SDK, ESP-IDF. It has robust community support, extensive documentation, and broad compatibility with wireless libraries and cloud services.

Teensy 4 development is primarily done through the Arduino IDE using the Teensyduino add-on. Although the community is smaller, it is active and well-supported. PJRC provides excellent documentation, especially for audio and real-time applications.

Conclusion

The ESP32 series is ideal for projects that require integrated wireless connectivity, low power operation, and sufficient processing for most embedded applications. It is particularly well-suited for IoT, wearable tech, and smart home systems.

The Teensy 4 series, with its powerful Cortex-M7 core, high-speed memory, and real-time capabilities, is perfect for applications requiring intensive computation, audio processing, and precise control. It excels in robotics, musical instruments, and industrial controls where raw performance is critical.

In summary, your choice between the ESP32 and Teensy 4 should depend on your project's connectivity, performance, and power requirements.

From IoT to Industrial: Copperhill Technologies' ESP32 and Teensy Boards

Copperhill Technologies offers a robust selection of embedded solutions tailored to developers working on industrial, automotive, and IoT applications. Their ESP32 WiFi, Bluetooth, Blue IoT Modules represent a versatile platform built on the Espressif ESP32 chipset, combining powerful wireless connectivity with low power consumption. With integrated CAN Bus, RS485, and Qwiic support, it's ideal for smart sensor networks, vehicle diagnostics, and remote monitoring systems, all in a compact, production-ready form factor.

For high-performance needs, Copperhill also features the Teensy 4.0 and 4.1 boards, based on the blazing-fast NXP Cortex-M7 processor. These boards excel in real-time processing, audio applications, and demanding industrial environments. With built-in CAN FD, multiple I/O options, and strong compatibility with Arduino and native development tools, the Teensy series from Copperhill provides an exceptional platform for engineers seeking reliability and speed in critical embedded projects.

Embedded Software for the IoT

Even the most conservative forecasts agree: the Internet of Things (IoT) represents a massive and rapidly growing market—one that demands constant innovation and skilled programmers. Yet developing for the IoT is uniquely challenging, as it spans a wide range of technical domains. Embedded Software for the IoT equips programmers with the foundational knowledge needed to thrive in this space, guiding them from core embedded programming concepts to real-world implementation strategies.

This book helps readers grasp the inner workings of the technologies powering modern IoT devices. It begins with an accessible overview of IoT and the design parameters of embedded systems, followed by essential best practices in coding, version control, and defect tracking—all crucial for building and maintaining connected systems.

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• Wired and wireless networking

• Digital filters

• Embedded and network system security

• Statistical process control for Industry 4.0

Ideal for software developers transitioning into embedded systems as well as experienced embedded engineers, this book offers a practical and comprehensive guide to the software side of IoT innovation. More information...