80 MHz Cortex-M4 with FPU — where it lands in the STM32L4 lineup
The 64-LQFP package gives you 52 I/O, a 16-channel 12-bit ADC, and a 2-channel 12-bit DAC — enough analog front-end for sensor-conditioning loops without an external converter.
128 KB Flash / 64 KB SRAM — sizing the firmware budget
The 128 KB Flash is the mid-density option in the STM32L433 family — enough for a moderate-complexity application stack (RTOS, USB stack, CANopen, sensor fusion library) without stepping up to the 256 KB or 512 KB variants. The 64 KB SRAM gives headroom for double-buffered display frames or a modest heap for dynamic allocation. If your firmware image is already pushing 100 KB, the STM32L433RCT6 (256 KB Flash) is the same footprint and pinout.
Connectivity and peripheral set — what the 52 I/O unlocks
The peripheral list includes CANbus, multiple I²C and SPI interfaces, a Quad-SPI for external Flash, SAI for audio, USB, and an LCD driver. The 52 I/O in the 64-LQFP package leave enough pins for a parallel LCD data bus, external memory chip selects, and a handful of sensor interrupts — you won't be multiplexing aggressively unless you need more than a dozen GPIOs for buttons and LEDs.
ST lists the STM32L433RBT6 as Active. For a production program that expects to run another three to five years, this part doesn't carry obsolescence risk. The ROHS3 compliance covers current EU and most global RoHS requirements without an exemption expiry to track.