Internally, each microcontroller consists of ARM processor core(s), flash memory, static RAM, debugging interface, and various peripherals.

The F1-series has evolved over time by increasing CPU speed, size of internal memory, variety of peripherals.

The summary for this series is:[24][25][23] The distinguishing feature for this series is presence of four fast, 12-bit, simultaneous sampling ADCs (multiplexer to over 30 channels), and four matched, 8 MHz bandwidth op-amps with all pins exposed and additionally internal PGA (Programmable Gain Array) network.

All analog devices can be completely independent, or partially internally connected, meaning that one can have nearly everything that is needed for an advanced measurement and sensor interfacing system in a single chip.

The four ADCs can be simultaneously sampled making a wide range of precision analog control equipment possible.

It is also possible to use a hardware scheduler for the multiplexer array, allowing good timing accuracy when sampling more than 4 channels, independent of the main processor thread.

[39] Digital filter for sigma-delta modulators (DFSDM) interface[32] The STM32 L0-series is the first group of STM32 microcontrollers based on the ARM Cortex-M0+ core.

The summary for this series is:[41][40] The STM32 L1-series was the first group of STM32 microcontrollers with a primary goal of ultra-low power usage for battery-powered applications.

An example of L4 MCU is STM32L432KC in UFQFPN32 package, that has: The STM32 L4+-series is expansion of STM32L4-series of ultra-low power microcontrollers, providing more performance, more embedded memory and richer graphics and connectivity features while keeping ultra-low-power capability.

Main features: The STM32 L5-series is an evolution of STM32L-series of ultra-low power microcontrollers: The STM32 U0-series is an entry-level addition to the STM32-series of ultra-low power microcontrollers: The STM32 U5-series is an evolution of STM32L-series of ultra-low power microcontrollers: The following boards have Arduino Nano pin-compatible male pin headers with 0.6-inch row-to-row DIP-30 footprint, but these boards have 3.3 volt logic I/O, instead of 5 volt logic I/O for an Arduino Nano.

All Nucleo boards by STMicroelectronics support the mbed development environment,[60][61] and have an additional onboard ST-LINK/V2-1 host adapter chip which supplies SWD debugging, virtual COM port, and mass storage over USB.

[70] Each board includes an on-board ST-LINK for programming and debugging via a Mini-B USB connector.

MicroEJ provides extended features to create, simulate, test and deploy Java applications in embedded systems.

All STM32 microcontrollers have a ROM'ed bootloader that supports loading a binary image into its flash memory using one or more peripherals (varies by STM32 family).

This method requires the target to have a way to enable/disable booting from the ROM'ed bootloader (i.e. jumper / switch / button).

A typical top-down documentation tree is: manufacturer website, manufacturer marketing slides, manufacturer datasheet for the exact physical chip, manufacturer detailed reference manual that describes common peripherals and aspects of a physical chip family, ARM core generic user guide, ARM core technical reference manual, ARM architecture reference manual that describes the instruction set(s).