STMicroelectronics STM8L050J3M3TR

Overview

STM8L050J3M3TR from STMicroelectronics is an 8-bit ultra-low-power microcontroller in SO8N package, featuring 8 Kbytes Flash, 256 bytes data EEPROM, RTC, 12-bit ADC (1 Msps), two 16-bit timers, USART/I²C/SPI interfaces, and dual ultra-low-power comparators. It operates from 1.8 V to 3.6 V across −40 °C to 125 °C and targets battery-powered sensor nodes and energy-harvesting systems requiring sub-µA Halt mode (350 nA) and fast 5 µs wakeup.

For engineers reviewing the STM8L050J3M3TR datasheet, STM8L050J3M3TR pinout, STM8L050J3M3TR application, or STM8L050J3M3TR equivalent, key selection criteria include verified 350 nA Halt current, RTC calendar with ±0.5 ppm digital calibration, 12-bit ADC accuracy at 2.4–3.6 V VDDA, and SWIM-based non-intrusive debugging support.

Technical Context

The STM8L050J3M3TR implements a Harvard-architecture STM8 core with 3-stage pipeline, delivering 16 CISC MIPS at 16 MHz max CPU frequency. Its clock system integrates three oscillators: factory-trimmed 16 MHz RC, 38 kHz low-consumption RC, and external 32 kHz crystal for RTC - all managed by a clock security system detecting oscillator failure.

Power management includes five programmable low-power modes: Wait (1.7 µA typ), Low-power Run (5.1 µA), Low-power Wait (3 µA), Active-Halt with RTC (1.3 µA), and Halt (350 nA). Each I/O exhibits ultra-low leakage (50 nA) and supports direct mapping to interrupt vectors for event-driven wake-up.

Key Specifications

Pinout & Package

STM8L050J3M3TR uses the SO8N (8-lead plastic small outline, 4.9 × 6 mm, 150 mils body width) package with standard gull-wing leads and RoHS-compliant ECOPACK® construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power 8-bit microcontroller applications.

Compared with STM8L050J3M3TR, STM8L052C6T6 offers scalability for complex firmware but increases size and cost, while RL78/G12 provides lower STOP current at the expense of 1.8 V compatibility and simplified debug - making STM8L050J3M3TR optimal for minimal-footprint, single-cell, time-stamped sensing.

Availability

STM8L050J3M3TR is available at Aetrix Electronics and suitable for smart metering, wireless sensor networks, energy harvesting systems, and portable medical devices requiring stable component supply and long-term lifecycle assurance.

Supply support for STM8L050J3M3TR 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 since 1987.

The STM8L Value line targets ultra-low-power embedded applications where battery life, cost, and design simplicity are critical - delivering robust 8-bit performance with industry-leading power efficiency down to sub-nanoampere levels.

FAQ

What is the minimum supply voltage for reliable operation of STM8L050J3M3TR?

The STM8L050J3M3TR operates reliably from 1.8 V to 3.6 V across its full temperature range (−40 °C to 125 °C). At 1.8 V, it supports all peripherals including the 12-bit ADC and RTC, with guaranteed 16 MHz CPU operation only above 2.95 V per datasheet Table 15. Brown-out reset thresholds are configurable down to 1.62 V for safe low-voltage shutdown.

Does STM8L050J3M3TR support in-system programming via SWIM?

Yes, STM8L050J3M3TR supports full-speed on-chip programming and non-intrusive debugging through the single-wire SWIM interface using only the SWIM pin and ground. No external debugger hardware is required - firmware updates can be performed in the field via USART bootloader or directly via SWIM with ST-LINK tools.

How is RTC accuracy maintained without external components?

The RTC achieves ±0.5 ppm accuracy via internal digital calibration against the LSE crystal, eliminating need for external trimming capacitors or temperature compensation circuits. The LSE security system detects crystal failure and automatically switches to backup RC oscillator while maintaining timekeeping integrity.

Can PA0 drive an LED directly without external current-limiting resistors?

PA0 supports high-sink LED driver capability (20 mA typical at VDD = 3.0 V), enabling direct connection of common-anode LEDs. However, a series resistor is still required to set precise current - e.g., 150 Ω for ~15 mA at 3.3 V - as PA0's VOL specification (0.4 V max) defines saturation voltage, not current regulation.