What the STM32L433RBI6 is and where it fits
The STM32L433RBI6 is a 32-bit ARM Cortex-M4 MCU from STMicroelectronics' STM32L4 ultra-low-power series, clocked at 80 MHz. It packs 128 KB of Flash and 64 KB of SRAM, with a rich peripheral set including USB, CAN, I²C, SPI, QSPI, and a 16-channel 12-bit ADC plus dual 12-bit DAC. The device is housed in a 64-UFBGA package and rated for -40°C to 85°C operation, making it suitable for industrial sensor nodes, portable instrumentation, and battery-powered field devices where low power draw and mixed-signal integration are critical.
80 MHz Cortex-M4 — what it means for throughput
The ARM Cortex-M4 core includes a single-precision FPU and DSP instructions, so the 80 MHz clock delivers real floating-point arithmetic and filter loops without a coprocessor. For a control loop or sensor fusion algorithm, that means tighter timing margins and simpler code compared to a Cortex-M3 at equivalent speed.
Memory and connectivity for a mixed-signal node
128 KB of Flash is enough for a moderate application stack plus a bootloader; 64 KB SRAM supports multi-packet USB buffers and a few kSamples of ADC data. The 16-channel 12-bit ADC can scan analog inputs while the dual 12-bit DAC drives control outputs, all without external converters. USB, CAN, and QSPI let this MCU talk to a host controller, a fieldbus gateway, or an external Flash memory — typical for a smart actuator or data-logging terminal.
Package and temperature grade
The 64-UFBGA (5x5 mm) package saves board area but requires careful PCB layout for the fine-pitch balls. The -40°C to 85°C range covers industrial environments — outdoor enclosures, factory floors, and engine compartments without active cooling.
Lifecycle and sourcing reality
The STM32L433RBI6 carries an eol_hot lifecycle flag, indicating the part is approaching end-of-life. While ST lists the product status as Active, buyers should plan for a last-time-buy window and evaluate pin-compatible alternatives within the STM32L4 family for long-term BOM stability. We source this part through independent distribution and quote it to order against an RFQ; availability and current pricing are confirmed at quote time.