STMicroelectronics STM32L100R8T6TR

Overview

STM32L100R8T6TR from STMicroelectronics is an ultra-low-power 32-bit ARM® Cortex®-M3 microcontroller with 128 KB Flash, 10 KB SRAM, 2 KB EEPROM, integrated LCD driver, USB 2.0 interface, and dual 12-bit DACs. It operates from 1.8–3.6 V, achieves 0.57 µA Stop mode current, and supports up to 32 MHz CPU frequency - deployed in battery-powered medical sensors and portable instrumentation requiring long runtime and analog signal conditioning.

For engineers reviewing the STM32L100R8T6TR datasheet, STM32L100R8T6TR pinout, STM32L100R8T6TR application, or STM32L100R8T6TR equivalent, key selection criteria include ultra-low-power mode timing (e.g., <8 µs wakeup), integrated true EEPROM endurance (100k cycles), LCD segment drive capability (8×28), and USB 2.0 full-speed compliance without external PHY.

Technical Context

The STM32L100R8T6TR implements a multi-voltage-domain architecture with dynamic voltage scaling (DVS) enabling three power-performance operating points: Low-power run (9 µA at 32 kHz), Run (214 µA/MHz at 32 MHz), and Stop/Standby modes with RTC retention. Its clock system integrates six independent sources - including HSE (1–24 MHz), LSE (32.768 kHz), HSI (16 MHz), LSI (37 kHz), MSI (65 kHz–4.2 MHz), and PLL - allowing precise trade-offs between timing accuracy, power, and wake-up latency.

Peripherals are partitioned across power domains: the LCD controller and USB PHY operate from dedicated regulators; ADC/DAC comparators share a common ultra-low-power analog reference; and all 51 I/Os support 5V tolerance in active mode with 10 nA leakage in Standby. Memory subsystem includes ECC-protected Flash and EEPROM, with 20-byte backup registers retained during full power-down.

Key Specifications

Pinout & Package

LQFP64 package (10 × 10 mm, 0.5 mm pitch), RoHS-compliant ECOPACK®2, with 51 fast I/Os - 42 of which are 5V tolerant and all mappable to 16 external interrupt vectors. Pin functions include VDD/VSS power rails, NRST reset, BOOT0 boot configuration, SWDIO/SWCLK debug, USB DP/DM, LCD segment/common outputs, and dedicated analog inputs for ADC/DAC/comparators.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32L100R8T6TR, STM32L053R8T6 trades LCD and dual DAC for crypto acceleration and smaller footprint, while STM32L432KCU6 offers higher compute headroom at the cost of display integration and EEPROM reliability - making STM32L100R8T6TR optimal for cost-sensitive, display-centric, battery-constrained instrumentation.

Availability

STM32L100R8T6TR is available at Aetrix Electronics and suitable for portable medical sensors, smart utility meters, industrial handheld terminals, and low-power IoT edge nodes requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for STM32L100R8T6TR 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 semiconductors since 1987.

The STM32L1 series targets ultra-low-power embedded applications demanding extended battery life, integrated analog peripherals, and robust memory integrity - optimized for wearable health monitors, smart meters, and portable industrial tools.

FAQ

What is the maximum operating frequency and associated power consumption of the STM32L100R8T6TR?

The STM32L100R8T6TR runs at up to 32 MHz in Run mode with typical current draw of 214 µA/MHz (≈6.85 mA total at 32 MHz, VDD = 3.3 V). This frequency is enabled by the internal 16 MHz HSI oscillator plus PLL multiplication, and is validated across the full temperature range (−40°C to +85°C) per datasheet Section 6.3.3.

Does the STM32L100R8T6TR support USB device functionality without external components?

Yes - it integrates a full-speed USB 2.0 transceiver with internal pull-ups on PA11 (DP) and PA12 (DM), requiring only standard USB connector wiring and decoupling capacitors. No external PHY, resistors, or crystal is needed, as the 48 MHz USB clock is generated internally via PLL from HSI or HSE sources.

How many I/O pins are 5V tolerant, and what is their safe operating voltage range?

42 of the 51 GPIOs are 5V tolerant in all modes except analog input mode. They safely accept DC voltages from −0.3 V to 5.5 V when configured as digital inputs or outputs, verified per datasheet Section 6.3.13. This simplifies interfacing with legacy 5V logic, displays, and sensors without level shifters.

What is the endurance and retention specification for the integrated EEPROM?

The 2 KB true EEPROM supports 100,000 write/erase cycles and guarantees 20-year data retention at 85°C (per datasheet Table 35). It features hardware wear leveling, ECC correction, and byte-level erase - unlike Flash-emulated EEPROM - making it suitable for storing calibration data, device IDs, and usage logs in field-deployed equipment.