STMicroelectronics STM8L101K3T3

Overview

STM8L101K3T3 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 remote control 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 - ideal for battery-powered sensor nodes and portable medical devices.

For engineers reviewing the STM8L101K3T3 datasheet, STM8L101K3T3 pinout, STM8L101K3T3 application, or STM8L101K3T3 equivalent, key selection criteria include ultra-low active/halt current, SWIM-based debug support, IR transmitter capability, 30 I/Os with LED driver (PA0), and UFQFPN32 package compatibility for space-constrained designs.

Technical Context

The STM8L101K3T3 implements a CISC-based STM8 core delivering up to 16 MIPS at 16 MHz, with dual internal RC oscillators: a 16 MHz HSI (typ. ±1% accuracy at 3 V) and a 38 kHz LSI for independent watchdog and auto-wakeup unit (AWU) timing. Its nested interrupt controller supports 29 external sources with software-configurable priority.

Memory architecture includes ECC-protected Flash with in-application programming, 2 Kbytes of data EEPROM, and flexible read/write protection. Power management integrates three low-power modes (Wait, Active-halt, Halt), POR/PDR circuitry, and voltage regulator monitoring - all optimized for sub-µA standby operation without external components.

Key Specifications

Pinout & Package

STM8L101K3T3 is housed in a 32-pin UFQFPN (5 × 5 mm, 0.5 mm pitch) package with exposed thermal pad. This leadless, space-efficient package supports reflow assembly and provides robust thermal performance for continuous low-power operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8L051F3P6, STM8L101K3T3 adds IR hardware and 4 KB more Flash; versus EFM8LB12F32ES1-QFP32, it trades raw memory for lower system BOM cost and zero-external-component IR capability.

Availability

STM8L101K3T3 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 production continuity.

Supply support for STM8L101K3T3 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 analog products for industrial, automotive, and consumer markets.

The STM8L series targets ultra-low-power embedded applications where energy efficiency, small footprint, and integrated peripherals reduce system-level complexity - especially in battery-operated and energy-harvesting designs.

FAQ

Does STM8L101K3T3 support in-circuit programming via SWIM?

Yes. The device features a hardware Single Wire Interface Module (SWIM) on PD3, enabling full-speed in-circuit programming and non-intrusive debugging without halting CPU execution. No external debugger hardware is required beyond a SWIM-capable programmer such as ST-LINK/V2-1.

What is the maximum clock frequency and how is it generated?

The STM8L101K3T3 runs at up to 16 MHz using its internal 16 MHz high-speed RC oscillator (HSI), which achieves ±1% typical accuracy at 3 V and 25 °C. An external crystal is not required, though optional for higher precision; the HSI supports fast wakeup in under 4 µs.

Can PA0 drive standard infrared LEDs directly?

Yes. PA0 is a dedicated high-sink LED/IR driver pin rated for 20 mA sink current at VDD ≥ 2.4 V. It supports direct connection of common 38 kHz IR LEDs (e.g., Vishay TSAL6100) without external transistors or current-limiting resistors beyond those specified in the IR carrier waveform design.

Is there hardware support for wake-up from Halt mode without external components?

Yes. The Auto-Wakeup Unit (AWU) uses the internal 38 kHz low-speed RC oscillator to generate periodic interrupts from Halt mode, enabling timed wake-up intervals from 122 µs to 8.4 s - all without external crystals, capacitors, or timing components.