SparkFun Thing Plus - STM32 - ARM® Cortex®-M4 32-bit RISC core - 1.8 V to 3.6 V Application Supply - an economical and Easy to use Development Platform - Adaptive Real-time Accelerator

With a 32-bit ARM Cortex-M4 RISC core, the SparkFun STM32 Thing Plus brings power and precision to your projects. The STM32 Thing Plus provides you with an economical and easy to use development platform if you're needing more power with a minimal working space. This Thing comes flashed with the DFU bootloader, and to make the Thing Plus even easier to use, we've moved a few pins around to make the board Feather compatible. In addition, it utilizes our handy Qwiic Connect System which means no soldering or shields are required to connect it to the rest of your system!
As we previously stated; the STM32F405 Processor is based on the high-performance ARM Cortex-M4 32-bit RISC core and can operate at a frequency of up to 168 MHz. The Cortex-M4 core features a floating point unit (FPU) single precision which supports all ARM single precision data-processing instructions and data types. It also implements a full set of DSP instructions and a memory protection unit (MPU) which enhances application security. This Processor Board utilizes the DFU bootloader for uploading code, and incorporates an extensive range of enhanced I/Os and peripherals. In addition to the USB interface and Qwiic connection, the STM32 Thing Plus provides a 3.3V regulator and LiPo charger as well as 16MB of Flash and microSD slot for expandable memory.
The SparkFun Qwiic Connect System is an ecosystem of I2C sensors, actuators, shields and cables that make prototyping faster and less prone to error. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector. This reduces the amount of required PCB space, and polarized connections mean you cant hook it up wrong.