80 MHz Cortex-M4 with 256 KB Flash — what this means for your BOM
The STM32L451CCU3 is an STMicroelectronics 32-bit MCU built around an ARM Cortex-M4 core clocked at 80 MHz, with 256 KB of Flash and 160 KB of SRAM. It sits in the STM32L4 ultra-low-power series, which means the 80 MHz clock is paired with a flexible power-management scheme — the core can run flat out for a control loop or DSP filter, then drop into a low-power sleep mode that draws microamps. For a BOM line, the 256 KB Flash / 160 KB SRAM combination is the mid-density sweet spot: enough headroom for a real-time OS or a moderate communications stack without forcing a move to a larger package or higher pin count.
Temperature grade and environment
Rated for -40°C to 125°C operating temperature, this MCU is qualified for environments where the ambient can swing from cold-soak to under-hood heat — industrial motor drives, outdoor telecom enclosures, and automotive body or chassis domains. The 48-UFQFN exposed pad package (7x7 mm) keeps the board footprint small, and the exposed pad helps conduct heat to the PCB ground plane, which matters when the core is running at 80 MHz in a sealed enclosure.
Connectivity and peripherals
On-chip peripherals include CANbus, I²C, SPI, UART/USART, IrDA, LINbus, QSPI, and SAI — a typical mix for an industrial sensor node or a CAN-connected actuator. The 38 I/O lines, 10-channel 12-bit ADC, and single 12-bit DAC cover analog front-end needs without an external converter. Brown-out detect, reset, DMA, PWM, and watchdog timer are built in, reducing external component count.