STMicroelectronics STM8S903F3P6TR

Overview

STM8S903F3P6TR from STMicroelectronics is an 8-bit MCU with 8 Kbytes Flash, 1 Kbyte RAM, and 640 bytes EEPROM, featuring a 16 MHz STM8 core, 10-bit ADC (7-channel), UART/SPI/I²C interfaces, and dual timers - deployed in industrial sensor nodes and low-cost motor control modules.

For engineers reviewing the STM8S903F3P6TR datasheet, STM8S903F3P6TR pinout, STM8S903F3P6TR application, or STM8S903F3P6TR equivalent, key selection criteria include operating voltage range (2.95–5.5 V), TSSOP20 package footprint, 20-pin I/O count with 21 high-sink outputs, and SWIM debug interface support.

Technical Context

The STM8S903F3P6TR implements a Harvard-architecture STM8 core with 3-stage pipeline and extended instruction set, supporting up to 16 MHz operation across its full voltage range. It integrates a nested interrupt controller servicing 32 interrupts, including up to 28 external sources mapped across 7 vectors.

Its clock system includes four master sources: low-power crystal oscillator, external clock input, user-trimmable 16 MHz RC, and 128 kHz low-power RC - all managed by a clock security system with dedicated monitor. Power management enables wait, active-halt, and halt modes with individual peripheral clock gating.

Key Specifications

Pinout & Package

TSSOP20 package (4.4 mm body width, 0.65 mm pitch), 7.0 × 4.4 × 1.2 mm profile, suitable for space-constrained industrial PCBs with manual or automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM8S003F3P6, the STM8S903F3P6TR adds 640-byte EEPROM for robust parameter storage; versus STM8L051F3P6, it delivers higher I/O sink capability and better noise immunity at the expense of higher active-mode current.

Availability

STM8S903F3P6TR is available at Aetrix Electronics and suitable for industrial sensor nodes, smart appliance control, energy metering subsystems, and entry-level motor drives requiring stable component supply and long-term production continuity.

Supply support for STM8S903F3P6TR 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 industrial, automotive, and consumer markets.

The STM8S series targets cost-sensitive, high-reliability embedded applications demanding robust I/O, integrated peripherals, and proven toolchain support - optimized for industrial automation and white-goods control.

FAQ

Does STM8S903F3P6TR support in-system programming via SWIM?

Yes. The STM8S903F3P6TR uses the Single Wire Interface Module (SWIM) on PC3 for in-circuit programming and debugging. It requires only one physical pin and supports full flash/EPPROM read/write, option byte configuration, and real-time variable inspection without halting execution.

What is the maximum operating frequency at 3.3 V supply?

The STM8S903F3P6TR operates up to 16 MHz across its full 2.95–5.5 V supply range, including at 3.3 V. This is confirmed in Section 10.3.1 of DS6210 Rev 13, which specifies f_CPUmax = 16 MHz at V_DD ≥ 2.95 V, with no derating required at 3.3 V.

Can TIM1 generate complementary PWM with programmable dead time?

Yes. TIM1 is a 16-bit advanced control timer with three complementary output channels and hardware-configurable dead-time insertion. Dead-time values are set via the DTG register (bits DTG[7:0]), supporting ranges from 1 to 1008 clock periods in discrete steps.

Is there a hardware I²C bus collision detection feature?

Yes. The I²C peripheral includes automatic arbitration loss detection and bus busy monitoring. When arbitration is lost during multi-master operation, the I²C_CR2 register's ARLO bit is set, and the peripheral halts transmission - enabling deterministic recovery in shared-bus systems.