80 MHz Cortex-M4 with FPU — the core that pulls DSP into the low-power domain
The STM32L476ZET6 is an STM32L4-series ARM Cortex-M4 MCU clocked at 80 MHz. That core includes a single-precision FPU and DSP instructions, so you can run sensor fusion, FFT, or PID loops without an external DSP — unusual for a part targeting sub-1 mA active draw. That 1.71 V floor is the real differentiator — many Cortex-M4 parts need 2.0 V minimum, which forces a boost stage in single-cell designs.
Peripheral mix — what the 114 I/O actually connects
The QSPI interface runs at up to 80 MHz, useful for memory-mapped external Flash. An LCD controller is baked in, so you can drive a segment LCD directly without an external driver chip — a cost saver in metering or HMI panels. The brown-out detect and watchdog peripherals are on-die, reducing external supervisor IC count.
Temperature grade and package — industrial, not automotive
It does not meet AEC-Q100 requirements, so avoid it for under-hood or cabin electronics. The 144-LQFP (20x20 mm) is a standard footprint with 0.5 mm pitch — the same as many STM32F4 and STM32L4 siblings, easing a pin-compatible swap if you need more Flash or a different peripheral set.
Lifecycle and sourcing posture
ST lists the STM32L476ZET6 as Active (current product). For new designs, there is no urgency to qualify a second source.