72 MHz Cortex-M3 with 160 KB flash in a 48-QFN
The CY9BF122KQN-G-AVE2 is an Infineon FM3 MB9B120M series microcontroller built around a 32-bit ARM Cortex-M3 core running at 72 MHz, with 160 KB of on-chip flash and 16K x 8 bytes of SRAM. The 72 MHz clock ceiling is set by the core architecture, not the flash wait-state profile — the Cortex-M3 pipeline and single-cycle multiply-accumulate give it enough throughput for motor-control loops and sensor-fusion algorithms that would stall a Cortex-M0 at the same frequency. Packaged in a 48-VFQFN with an exposed pad (7x7 mm), it routes 35 I/O pins and the power/ground ring to a single ground paddle that pulls heat into the PCB copper pour — the thermal pad is the primary heat path, not the package body.
Peripheral set and connectivity for sensor-heavy designs
On the analog side it carries a 14-channel 12-bit ADC and a 2-channel 10-bit DAC — the ADC scans through the multiplexer at up to 1 Msps, so a single conversion sequence can sample three phase currents and a DC-bus voltage in under 5 µs. For serial interfaces it supports CSIO, I²C, LINbus, and UART/USART — the LIN controller is useful for automotive body-node communication, while the I²C and UART ports handle sensor bridges and debug consoles without an external USB-UART bridge. The DMA controller offloads peripheral-to-memory transfers from the Cortex-M3 core — a UART receive stream or ADC conversion sequence runs in the background while the CPU executes the control loop, keeping the effective throughput closer to the 72 MHz ceiling.
Active lifecycle and sourcing posture
The part is RoHS3 compliant and supplied in tray packaging — the 48-QFN footprint is standard across the FM3 MB9B120M family, so a single PCB layout serves multiple flash and RAM variants if the BOM needs to flex.