Active production — no near-term EOL risk
The STM32L471RET3TR: This is the baseline for any new design: you can commit the BOM line without a last-time-buy clock ticking.
This is an STMicroelectronics STM32L471RET3TR, a 32-bit ARM Cortex-M4 single-core MCU from the STM32L4 ultra-low-power series. The 128 KB SRAM gives enough workspace for double-buffered sensor data or a modest TCP/IP buffer pool.
Peripheral set — CAN, QSPI, SAI, and a dozen serial interfaces
Connectivity covers CANbus, I²C, IrDA, LINbus, MMC/SD, QSPI, SAI, SPI, SWPMI, and UART/USART. The QSPI interface is useful for memory-mapped external Flash or RAM without chewing up GPIO. The SAI (serial audio interface) handles I²S audio codecs or time-division multiplexed data streams. With 51 general-purpose I/O in a 64-LQFP package, you get a reasonable pin count for a mixed-signal control board without the routing complexity of a larger BGA. On-chip data converters include a 16-channel 12-bit ADC and a 2-channel 12-bit DAC, enough for analog sensor readout and closed-loop analog output without external converters.
Package and supply — 64-LQFP, Tape & Reel
The STM32L471RET3TR comes in a 64-LQFP package with a 10x10 mm body, surface-mount. If your line runs tubes or trays, the base part number STM32L471RET6 (without the TR suffix) is the tray variant; verify availability separately. The 64-LQFP footprint is a common, low-cost package with a 0.5 mm pitch — easy to route on a two-layer board and reworkable with a hot-air station.