What this MCU brings to the board
The STM32L433RCY3TR is a 32-bit ARM Cortex-M4 MCU from STMicroelectronics' STM32L4 ultra-low-power series, clocked at 80 MHz with a single-precision FPU. It carries 256 KB of Flash and 64 KB of SRAM.
Temperature range and deployment environment
Rated for -40°C to 125°C ambient, this part is suited for industrial and automotive under-hood environments where the PCB sees wide thermal swings — outdoor telecom cabinets, engine-bay controllers, or factory-floor sensor nodes. The wide span eliminates the need for a separate industrial-temperature variant in mixed-ambient builds.
Peripherals and connectivity
On-chip peripherals include brown-out detect, DMA, a segment LCD controller, PWM timers, and a watchdog. Connectivity covers CANbus, I²C, IrDA, LINbus, MMC/SD, QSPI, SAI, SPI, SWPMI, UART/USART, and USB — enough to interface with most industrial fieldbuses and external memory without glue logic. The 52 I/O lines give headroom for parallel sensor arrays or a local HMI keypad.
Sourcing and lifecycle reality
The manufacturer lists this part as Active, though some distribution channels flag an end-of-life hot status. For a BOM line that needs long-term supply assurance, the safest move is to quote against an RFQ and confirm current availability at order time. The base product number STM32L433 opens the door to pin-compatible density variants in the same WLCSP footprint if a last-time-buy or alternate source is needed later.