STMicroelectronics STM32L412KBT6

Overview

STM32L412KBT6 from STMicroelectronics is an ultra-low-power Arm® Cortex®-M4 32-bit MCU with FPU, operating up to 80 MHz (100 DMIPS), featuring 128 KB flash, 40 KB SRAM, and integrated analog peripherals including dual 12-bit ADCs (5 Msps), one operational amplifier with PGA, and one ultra-low-power comparator. It supports external SMPS for optimized efficiency and targets battery-powered IoT sensors, portable medical devices, and smart metering endpoints requiring sub-1 µA standby current and RTC-backed operation.

For engineers reviewing the STM32L412KBT6 datasheet, STM32L412KBT6 pinout, STM32L412KBT6 application, or STM32L412KBT6 equivalent, key selection criteria include its 28 µA/MHz run-mode current at 3.3 V with SMPS, 245 nA standby-with-RTC power draw, LPUART wake-up capability in Stop 2 mode, and QSPI XIP support for external code execution - all critical for energy-constrained embedded designs.

Technical Context

The STM32L412KBT6 implements FlexPowerControl architecture with seven low-power modes (Shutdown, Standby, Stop 0/1/2, Sleep, Run), enabling dynamic voltage scaling and automatic transition between LDO and external SMPS regulation. Its ART Accelerator™ delivers zero-wait-state execution from flash at 80 MHz, while the interconnect matrix decouples bus arbitration for concurrent peripheral access without CPU intervention.

Core timing relies on multiple clock sources: 4–48 MHz HSE crystal, 32 kHz LSE for RTC, factory-trimmed 16 MHz HSI (±1%), and auto-calibrated MSI (±0.25% accuracy via LSE). The USB 2.0 full-speed interface operates without external crystal using internal clock recovery, reducing BOM count in space-constrained applications.

Key Specifications

Pinout & Package

STM32L412KBT6 is housed in a 32-pin UFQFPN package (5 mm × 5 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions are validated per STMicroelectronics' DS12469 Rev 9, Section 4 "Pinouts and pin description", and include dedicated VDD/VSS rails, reset (NRST), BOOT0, SWDIO/SWCLK debug, and multiplexed AF-capable GPIOs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power MCU applications.

Compared with STM32L432KBU6, the STM32L412KBT6 trades crypto acceleration for Quad-SPI XIP - enabling scalable firmware storage without external RAM. Against STM32L072KBU6, it delivers 3× higher DMIPS and 40% lower standby current, making it superior for latency-sensitive, energy-critical edge nodes.

Availability

STM32L412KBT6 is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical devices, smart utility meters, and industrial predictive maintenance systems requiring stable component supply across multi-year production cycles.

Supply support for STM32L412KBT6 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and automotive-grade components.

The STM32L4 series targets ultra-low-power embedded applications demanding high performance-per-milliwatt, combining Cortex-M4 efficiency with ST's proprietary power gating and analog integration for battery-operated and energy-harvesting systems.

FAQ

What is the maximum operating frequency and corresponding performance metric?

The STM32L412KBT6 runs at up to 80 MHz with an Adaptive Real-Time Accelerator (ART) enabling zero-wait-state execution from flash. Its performance is rated at 100 DMIPS (Dhrystone 2.1), achieving 1.25 DMIPS/MHz, and scores 273.55 CoreMark® (3.42 CoreMark/MHz), verified under standard test conditions with ART enabled and prefetch disabled.

Does STM32L412KBT6 support external SMPS, and how does it affect power efficiency?

Yes - the device supports external SMPS via VDD12 input, reducing core voltage to 1.1 V. This configuration cuts active-mode current to 28 µA/MHz (vs. 79 µA/MHz with internal LDO), delivering >65% reduction in dynamic power. SMPS mode requires external regulator control via PWR_CR3[1] bit and proper PCB layout for noise isolation.

Can the integrated op-amp drive external loads directly, and what are its key electrical limits?

The single rail-to-rail op-amp supports unity-gain stable operation with programmable gain (1–40x via internal PGA), 1.5 MHz GBW, and ±10 mA output drive. It is specified for VDDA = 1.62–3.6 V and draws 85 µA typical. Output swing is limited to VDDA – 0.2 V / VSS + 0.1 V, and it cannot drive capacitive loads >100 pF without external compensation.

Is the STM32L412KBT6 qualified for industrial temperature range, and what are its absolute maximum ratings?

Yes - the KBT6 variant is rated for –40 °C to +85 °C ambient operation. Absolute maximum ratings include VDD/VDDA = –0.3 V to +4.0 V, I/O pin voltage = –0.3 V to VDD + 4.0 V (5 V-tolerant on most pins), and junction temperature ≤ +125 °C. Exceeding these values risks permanent damage per STMicroelectronics' DS12469 Rev 9, Section 6.2.