120 MHz Cortex-M4 with 2 MB flash — memory headroom for GUI and OTA
The STM32L4R9AII6 is a 32-bit single-core MCU built around the ARM Cortex-M4 core clocked at 120 MHz. With 2 MB of on-chip Flash and 640 KB of SRAM, this part can host a full GUI framework, dual-bank firmware-over-the-air, or a sensor fusion stack without external memory. The 131 I/O lines give ample room for parallel displays, memory-mapped peripherals, and fieldbus interfaces.
Package and board integration — 169-UFBGA 7x7 mm
Housed in a 169-ball UFBGA measuring 7x7 mm, the package demands a fine-pitch BGA assembly process and a 4-layer or more PCB for fan-out. The 0.50 mm ball pitch is typical for this density — ensure the solder mask registration and stencil aperture are matched to the land pattern in the STM32L4R9 reference design. Surface-mount only.
Connectivity and data conversion — CAN, USB OTG, dual DAC
The 14-channel 12-bit ADC and two 12-bit DAC channels handle analog sensor inputs and audio or control outputs.
