STMicroelectronics STM32U073KBU6

Overview

STM32U073KBU6 from STMicroelectronics is an ultra-low-power Arm® Cortex®-M0+ 32-bit MCU operating up to 56 MHz, featuring 256-Kbyte flash memory, 40-Kbyte SRAM with hardware parity, and integrated USB 2.0 full-speed crystal-less interface. It delivers 407 ULPMark™-CP and supports VBAT mode at 130 nA with RTC + 9×32-bit backup registers - deployed in battery-powered medical sensors and portable industrial monitors.

For engineers reviewing the STM32U073KBU6 datasheet, STM32U073KBU6 pinout, STM32U073KBU6 application, or STM32U073KBU6 equivalent, key selection criteria include shutdown current (16 nA), Stop 2 mode power (695 nA without RTC), 12-bit ADC with 0.4 µs conversion, LCD driver (8×48 segments), and 69 GPIOs (5 V-tolerant on most pins).

Technical Context

The STM32U073KBU6 integrates a Cortex-M0+ core with ART Accelerator enabling 0-wait-state execution from flash at 56 MHz, and features dual-regulator power architecture (MR/LPR) supporting dynamic switching between Run (52 μA/MHz) and Stop 2 (695 nA) modes. Its analog subsystem includes independent VDDA supply, 12-bit DAC with sample-and-hold, and operational amplifier with programmable gain up to 16.

USB functionality uses internal 48 MHz clock recovery (HSI48) eliminating external crystal requirement; RTC operates from LSE (32 kHz) or VBAT with automatic switchover logic. Security includes RDP Level 2 (irreversible), HDP, secure boot, and NIST SP 800-90B–candidate TRNG.

Key Specifications

Pinout & Package

STM32U073KBU6 is housed in a 48-pin UFQFPN package (7 × 7 mm, 0.5 mm pitch), RoHS-compliant and ECOPACK2 certified. Pin functions are validated per DS14548 Rev 2 (pages 42–47) and match the UFQFPN48 mechanical drawing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power Cortex-M0+ MCU applications.

Compared with STM32L073RZT6, the STM32U073KBU6 reduces shutdown current by 85% and adds crystal-less USB; versus STM32U575ZIT6, it trades raw compute for 4× lower shutdown power and integrated LCD - making it optimal for long-life, display-equipped edge sensors.

Availability

STM32U073KBU6 is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, industrial wireless sensor nodes, and portable diagnostic tools requiring stable component supply across multi-year production cycles.

Supply support for STM32U073KBU6 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 ICs, sensors, and automotive semiconductors since 1987.

The STM32U0 series targets ultra-low-power battery-operated applications demanding sub-100 nA shutdown, integrated analog peripherals, and secure firmware execution - extending runtime in medical, metering, and portable industrial devices.

FAQ

What is the minimum supply voltage for reliable operation of STM32U073KBU6?

The STM32U073KBU6 operates reliably from 1.71 V to 3.6 V on VDD. Below 1.71 V, brownout reset (BOR) activates at configurable thresholds; the device guarantees full functionality-including 56 MHz CPU operation and 12-bit ADC accuracy-down to 1.71 V with LDO enabled. VDDA must be ≥1.62 V for ADC/COMP or ≥2.4 V for VREFBUF operation.

Does STM32U073KBU6 support true hardware AES encryption?

No. The STM32U073KBU6 does not include a dedicated AES accelerator. It provides secure boot, RDP Level 2, HDP, and TRNG-but cryptographic operations like AES must be implemented in software using the Cortex-M0+ core. For hardware-accelerated AES, consider STM32U5 or STM32L5 series devices.

Can the internal 12-bit DAC drive a speaker directly?

No. The DAC output channel is designed for precision analog signal generation-not power delivery. Its typical output drive capability is ±5 mA into resistive loads; driving even a small 8 Ω speaker would cause severe distortion and exceed absolute maximum ratings. Use an external audio amplifier stage (e.g., Class-D or opamp buffer) for speaker interfacing.

How many GPIOs on STM32U073KBU6 are 5 V-tolerant in all power modes?

68 of the 69 GPIOs are 5 V-tolerant when VDD is powered between 1.71 V and 3.6 V. Tolerance is maintained in Run, Sleep, Stop, and Standby modes-but not in Shutdown mode, where I/Os enter high-impedance state and 5 V tolerance is undefined. Pin PA0 is not 5 V-tolerant; consult Table 10 in DS14548 Rev 2 for full pin listing.