The 4 KB SRAM (organized as 4K x 8) leaves room for a modest stack and a few buffers; heap-heavy applications or large lookup tables will push the limit. On-chip peripherals include DMA, a watchdog timer, PWM-capable timers, a temperature sensor, and POR/PVD/PDR reset management.
Package and power — 36-VFQFPN with exposed pad for compact boards
Housed in a 36-VFQFPN (6x6 mm) with an exposed thermal pad, this MCU suits space-constrained PCBs where heat spreading matters. The 26 I/O lines in this package count are enough for a keypad, a small character LCD, and a few sensor inputs — but if you need more than 26 GPIO, step up to the 48-pin or 64-pin STM32F101 variants.
For dual-sourcing or a higher-density drop-in, the STM32F101 family shares the same pinout across Flash density options in the same package — a 32 KB or 64 KB sibling in the 36-VFQFPN footprint will fit the same board with a firmware update.