40 MHz ARM Cortex-M3 with 256 KB Flash — what it buys the design
The Infineon CY9AF314NAPMC-GNE2 is a 32-bit ARM Cortex-M3 microcontroller from the FM3 MB9A310A series, clocked at 40 MHz. The 2.7 V to 5.5 V supply range is a practical advantage: it runs directly from a 3.3 V or 5 V rail, or from a 3-cell alkaline battery stack, without a regulator. With 83 general-purpose I/Os in a 100-LQFP package, this part suits control panels, sensor hubs, and human-machine interface applications where a single-chip solution keeps the BOM count low.
Memory and peripheral budget for the BOM
A typical application — say, a brushless DC motor controller with CANopen stack and USB logging — fits comfortably in 128 KB of code space, leaving headroom for field-upgradeable bootloader and diagnostic routines. The 32 KB RAM supports moderate-sized data buffers and a real-time OS kernel with a few tasks. The 16-channel 12-bit SAR ADC samples at rates adequate for current sensing in motor drives or multi-channel temperature monitoring. The DMA controller offloads ADC result transfers and serial communication without CPU intervention, preserving the 40 MHz core for control algorithm execution.
The 83 I/Os are distributed around all four sides, giving the layout engineer flexibility in signal routing. No exposed thermal pad — junction-to-ambient thermal performance relies on the leadframe and copper pour area.
For dual-sourcing or a higher-performance variant, the CY9BF314RPMC-G-JNE2 is a pin-compatible sibling in the FM3 MB9B310R series, running at 144 MHz with the same 256 KB Flash and 100-LQFP footprint.