STMicroelectronics STM32L433RBT6

Overview

STM32L433RBT6 from STMicroelectronics is an ultra-low-power Arm® Cortex®-M4 32-bit MCU with FPU, operating up to 80 MHz (100 DMIPS), featuring 256 KB flash, 64 KB SRAM, USB FS, LCD controller, and integrated SMPS support. It delivers 36 µA/MHz in SMPS-run mode, 280 nA Standby with RTC, and supports capacitive touch sensing for battery-powered human-interface applications.

For engineers reviewing the STM32L433RBT6 datasheet, STM32L433RBT6 pinout, STM32L433RBT6 application, or STM32L433RBT6 equivalent, key selection criteria include ultra-low-power operation across Stop/Standby modes, LCD + touch integration, USB crystal-less full-speed capability, and dual-supply (LDO/SMPS) flexibility for energy-constrained embedded systems.

Technical Context

The device integrates an Adaptive Real-time Accelerator (ART™) enabling zero-wait-state execution from flash at 80 MHz, paired with a Memory Protection Unit (MPU) and dual PLLs-one dedicated to USB clock recovery. Its interconnect matrix enables concurrent peripheral access without bus contention.

Low-power operation is architecturally enforced via FlexPowerControl: five distinct low-power modes (Shutdown, Standby, Stop 2, Low-power Run, and Run), each with configurable voltage scaling and clock gating. The 32-bit Cortex-M4 core includes DSP instructions and a single-precision FPU for sensor fusion and real-time control tasks.

Key Specifications

Pinout & Package

LQFP64 package (10 × 10 mm, 0.5 mm pitch), RoHS-compliant ECOPACK2, with exposed thermal pad for enhanced thermal dissipation in continuous operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power ARM Cortex-M4 MCU applications.

Compared with STM32L476RGT6 and STM32L552RET6, the STM32L433RBT6 uniquely balances ultra-low-power operation, integrated LCD + capacitive touch, and USB crystal-less capability-making it optimal for cost-sensitive, battery-powered HMIs where display, touch, and minimal BOM are primary design constraints.

Availability

STM32L433RBT6 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial sensor nodes, and portable medical diagnostic tools requiring stable component supply and long-term lifecycle assurance.

Supply support for STM32L433RBT6 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, MEMS, and automotive semiconductors.

The STM32L4 series targets ultra-low-power embedded applications demanding extended battery life, rich analog integration, and secure firmware execution-optimized for portable medical, industrial sensing, and smart metering use cases.

FAQ

What is the maximum operating frequency and corresponding power consumption of STM32L433RBT6 in SMPS mode?

The STM32L433RBT6 operates at up to 80 MHz with 36 µA/MHz current draw when powered by external SMPS (VDD12 = 1.10 V). At full speed, this yields ~2.88 mA total active current - verified per Table 27 in DS11449 Rev 8. This efficiency enables sustained real-time processing in energy-harvesting systems.

Does STM32L433RBT6 support crystal-less USB Full-Speed operation?

Yes. The device integrates a clock recovery system (CRS) that locks to the USB SOF packet, enabling crystal-less USB 2.0 Full-Speed operation with ±0.25% accuracy. This eliminates the need for a 48 MHz crystal, associated load capacitors, and ESD protection components - confirmed in Section 3.34 and Table 6.3.34 of the datasheet.

How many capacitive touch sensing channels does STM32L433RBT6 provide, and what is their implementation method?

The STM32L433RBT6 provides 21 dedicated capacitive sensing channels via its Touch Sensing Controller (TSC), supporting touchkey, linear, and rotary sensors using charge-transfer measurement. All channels are implemented in hardware with automatic scan sequencing and noise immunity features - detailed in Section 3.20 and Table 2 of DS11449 Rev 8.

What LCD configurations are supported, and does the device include a built-in step-up converter?

The STM32L433RBT6 supports LCD configurations up to 8×40 segments or 4×44 segments and includes an integrated step-up converter capable of generating up to 5.2 V from a 3.3 V supply. This allows direct driving of common LCD glass requiring higher bias voltages without external boost ICs - specified in Section 3.21 and Table 6.3.25.