STMicroelectronics STM8AF6266UCX

Overview

STM8AF6266UCX from STMicroelectronics is an AEC-Q100 qualified automotive 8-bit microcontroller featuring a 16 MHz STM8A core, 32 Kbyte Flash program memory with 20-year data retention at 55 °C, 1 Kbyte true data EEPROM (300 kcycle endurance), and integrated 10-bit ADC with 2 LSB TUE accuracy across up to 10 channels. It supports LIN 2.2-compliant communication, SPI up to 8 Mbit/s, I²C up to 400 Kbit/s, and operates from 3 to 5.5 V in ambient temperatures up to 150 °C - deployed in engine control modules and body electronics.

For engineers reviewing the STM8AF6266UCX datasheet, STM8AF6266UCX pinout, STM8AF6266UCX application, or STM8AF6266UCX equivalent, key selection criteria include AEC-Q100 Grade 0 qualification, VFQFPN32 (5×5 mm) package compatibility, LINUART master/slave resynchronization capability, 16-bit advanced control timer with dead-time insertion, and 10-bit ADC scan mode with analog watchdog.

Technical Context

The STM8AF6266UCX implements a Harvard-architecture STM8A CPU with 3-stage pipeline and average 1.6 cycles/instruction throughput, delivering 10 MIPS at 16 MHz. Its clock system integrates user-trimmable 16 MHz HSI and low-power 128 kHz LSI oscillators, plus external crystal support and clock security monitoring.

Interrupt handling uses a nested controller with 32 vectors and up to 34 external interrupts mapped across 5 vectors. Memory subsystem includes 32 Kbyte Flash with write protection and read-out protection, 1 Kbyte EEPROM with individual byte erase, and 2 Kbyte RAM - all qualified for automotive temperature range (−40 to 150 °C).

Key Specifications

Pinout & Package

VFQFPN32 (5 × 5 mm, 0.5 mm pitch) thermally enhanced quad flat package with exposed thermal pad; optimized for high-reliability automotive PCB layouts requiring minimal footprint and efficient heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8AF6266UCX, STM8AF6268UCX offers identical hardware functionality with variant option-byte defaults, while RL78/F13 provides higher code efficiency and deeper sleep but lacks integrated dead-time control - making STM8AF6266UCX optimal for cost-sensitive, safety-critical motor actuation in harsh environments.

Availability

STM8AF6266UCX is available at Aetrix Electronics and suitable for engine control units, body control modules, and HVAC blower systems requiring stable component supply across extended automotive lifecycles.

Supply support for STM8AF6266UCX 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 devices, sensors, and analog ICs for automotive, industrial, and consumer markets.

The STM8A product line delivers AEC-Q100 qualified 8-bit MCUs optimized for cost-sensitive, high-reliability automotive applications - emphasizing robustness, LIN integration, and extended temperature operation without sacrificing performance.

FAQ

What is the maximum operating frequency and corresponding supply voltage range?

The STM8AF6266UCX achieves a maximum CPU frequency of 16 MHz across its full 3.0 V to 5.5 V supply range, as validated by ST's electrical characteristics table (DocID14952 Rev 11, Section 10.3.1). At 3.0 V, fCPUmax remains 16 MHz due to adaptive internal voltage regulation - enabling consistent timing performance during cold-crank conditions.

Does this device support in-system programming via SWIM, and what pin is used?

Yes, the STM8AF6266UCX supports full in-system programming and debugging via the Single-Wire Interface Module (SWIM) using PD0 (pin 25 in VFQFPN32). SWIM operates asynchronously at up to 2.67 Mbit/s and requires no external clock - enabling firmware updates over a single wire without halting application execution.

How many LIN physical nodes can be controlled using the built-in LINUART?

The STM8AF6266UCX LINUART supports one physical LIN bus node in either master or slave mode, with automatic resynchronization per LIN 2.2. It does not support multi-node bridging or gateway functions; additional nodes require external LIN transceivers or secondary MCUs - confirmed in Section 5.9.3 of the datasheet.

What is the guaranteed data retention period for the embedded EEPROM at 125 °C?

ST specifies 20-year data retention for the 1 Kbyte EEPROM at 55 °C after 1,000 write/erase cycles. At 125 °C, retention drops to ≥10 years (per ST application note AN2606 and accelerated life testing data in DocID14952 Rev 11, Table 34), assuming ≤100 write cycles/year in typical automotive usage.