STMicroelectronics STM8AL3166UAX

Overview

STM8AL3166UAX from STMicroelectronics is an AEC-Q100 qualified automotive-grade 8-bit ultra-low-power MCU featuring 32 Kbyte Flash, 2 Kbyte RAM, 1 Kbyte data EEPROM, 12-bit ADC (25 channels, up to 1 Mbps), 12-bit DAC with output buffer, two ultra-low-power comparators, RTC with BCD calendar and auto-wakeup (0.95 ppm resolution), and support for LIN 2.0/1.3, IrDA, and ISO 7816 on USART - deployed in battery-powered vehicle body controllers and smart sensor nodes.

For engineers reviewing the STM8AL3166UAX datasheet, STM8AL3166UAX pinout, STM8AL3166UAX application, or STM8AL3166UAX equivalent, key selection criteria include ultra-low-power operation down to 400 nA in Halt mode with PDR, 1.65–3.6 V supply range, -40 °C to 125 °C extended temperature grade, LQFP32 package compatibility, and SWIM-based non-intrusive debugging support.

Technical Context

The STM8AL3166UAX implements a Harvard-architecture STM8 core with 3-stage pipeline, delivering 16 CISC MIPS at 16 MHz max frequency and supporting up to 40 external interrupt sources. Its clock system integrates dual crystal oscillators (1–16 MHz HSE and 32 kHz LSE), factory-trimmed 16 MHz RC, and 38 kHz low-consumption RC with clock security system.

Power management includes five configurable low-power modes: Wait (typ. 5.1 μA), low-power Wait (3 μA), active-halt with full RTC (1.3 μA), and Halt with PDR (400 nA). The RTC operates independently with periodic wakeup capability and maintains calendar accuracy across temperature and voltage variations.

Key Specifications

Pinout & Package

LQFP32 (7 × 7 mm, 0.8 mm pitch) package with 32 pins, thermally enhanced for automotive ambient conditions and compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8AL3166UAX, STM8AL3168UAX offers identical functionality with factory bootloader integration, while STM32L011K4T6 trades automotive-optimized low-power analog features and LIN hardware for 32-bit compute headroom - making the STM8AL3166UAX optimal for cost-sensitive, function-specific automotive body electronics.

Availability

STM8AL3166UAX is available at Aetrix Electronics and suitable for automotive body control modules, smart actuator nodes, TPMS sensor hubs, and engine-bay environmental monitors requiring stable component supply across extended product lifecycles.

Supply support for STM8AL3166UAX 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 STM8AL3x series is part of ST's automotive ultra-low-power MCU portfolio, engineered specifically for battery-sensitive vehicle body electronics where extended sleep current, AEC-Q100 compliance, and integrated LIN/RTC functionality are mandatory.

FAQ

What is the minimum supply voltage for reliable operation in Halt mode?

The STM8AL3166UAX supports Halt mode with power-down reset (PDR) down to 1.65 V, drawing only 400 nA typical current. Below 1.65 V, the device enters power-down state with retained RAM and registers until VDD rises above the BOR threshold - critical for maintaining state during battery sag in start-stop systems.

Does STM8AL3166UAX support LIN physical layer without external transceiver?

No. While the USART hardware implements LIN protocol framing (break detection, sync, checksum), a compliant LIN transceiver (e.g., TLE7259-3GE) is required for bus-level signaling, ESD protection, and voltage level translation. The MCU provides full protocol stack support but not physical layer drive capability.

How many I/O pins support external interrupt capability in LQFP32 package?

All 29 general-purpose I/O pins (PA0–PA7, PB0–PB7, PC0–PC7, PD0–PD7) in the LQFP32 variant are individually mappable to external interrupt vectors. Each pin can trigger interrupt on rising/falling edge or level, with priority managed by the nested interrupt controller.

Is the 12-bit DAC output buffered and rail-to-rail?

Yes. The integrated 12-bit DAC features an internal output buffer with rail-to-rail swing (VSS to VDD), available on PB4, PB5, and PB6. It supports continuous waveform generation and has guaranteed monotonicity and ±2 LSB INL across the full operating temperature range.