STMicroelectronics STM8L101K3U6TR

Overview

STM8L101K3U6TR from STMicroelectronics is an 8-bit ultra-low-power microcontroller featuring 8 Kbytes Flash, 1.5 Kbytes RAM, and integrated peripherals including two 16-bit timers, USART, SPI, I²C, two comparators, and infrared (IR) interface. It operates from 1.65 V to 3.6 V across –40 °C to +85 °C, with Halt-mode current as low as 0.3 µA - designed for battery-powered sensor nodes and portable medical devices.

For engineers reviewing the STM8L101K3U6TR datasheet, STM8L101K3U6TR pinout, STM8L101K3U6TR application, or STM8L101K3U6TR equivalent, key selection criteria include ultra-low active/halt current, SWIM-based debug support, IR modulation capability, and 20-pin UFQFPN (3 × 3 mm) package compatibility with space-constrained PCB layouts.

Technical Context

The STM8L101K3U6TR implements the STM8 CISC core delivering up to 16 MIPS at 16 MHz, with dual internal oscillators: a 16 MHz high-speed RC (HSI) for dynamic run mode and a 38 kHz low-power RC (LSI) for independent watchdog and auto-wakeup unit (AWU) operation. Its nested interrupt controller supports up to 29 external sources with software-configurable priority.

Memory architecture includes ECC-protected Flash with in-application programming, 2 Kbytes of emulated data EEPROM, and 1.5 Kbytes of static RAM. Clock management integrates prescalers, switchable oscillator sources, and automatic clock switching during low-power transitions - enabling deterministic wake-up from Halt in ≤4 µs via AWU or external interrupt.

Key Specifications

Pinout & Package

STM8L101K3U6TR uses the UFQFPN20 (3 × 3 mm, 0.5 mm pitch) package - a space-efficient, thermally enhanced quad flat no-lead solution optimized for compact wearable and IoT endpoint designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8L101K3U6TR, STM8L051F3P6 trades IR capability for lower cost and TSSOP compatibility, while EFM8LB12F32ES1 offers more memory and USB but increases component count and timing complexity for IR applications.

Availability

STM8L101K3U6TR is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical monitors, smart home remotes, and industrial status indicators requiring stable component supply and long-term manufacturability.

Supply support for STM8L101K3U6TR 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 analog components for industrial, automotive, and consumer markets.

The STM8L101 series belongs to ST's ultra-low-power 8-bit MCU product line, engineered specifically for energy-constrained applications where sub-µA sleep current, fast wake-up, and integrated analog peripherals reduce system-level BOM cost and PCB area.

FAQ

Does STM8L101K3U6TR support in-application programming (IAP) of Flash memory?

Yes. The device supports full in-application programming of Flash memory via its built-in bootloader, allowing firmware updates without halting main application execution. IAP is enabled through dedicated Flash programming registers and requires proper sector locking/unlocking sequence per ST's AN2659 application note.

What is the maximum clock frequency achievable with the internal 16 MHz RC oscillator?

The internal high-speed RC (HSI) oscillator is factory-trimmed to ±1% accuracy at 25 °C and 3.0 V, supporting sustained 16 MHz operation across the full 1.65–3.6 V supply range and –40 to +85 °C temperature range. No external crystal is required for full-speed operation.

Can PA0 be used simultaneously as an IR driver and a general-purpose I/O?

No. PA0 serves as the dedicated IR output channel when the IR peripheral is enabled. In that mode, it is functionally locked to IR carrier generation and cannot be used as a standard GPIO. When IR is disabled, PA0 reverts to a high-sink-capable I/O with 20 mA sink capability.

Is SWIM debug supported on all package variants of STM8L101K3U6TR?

Yes. SWIM (Single Wire Interface Module) is implemented identically across all STM8L101x3 variants, including the UFQFPN20-packaged STM8L101K3U6TR. Debug access requires only the SWIM pin, NRST, VDD, and VSS - no additional debug headers or JTAG pins needed.