STM8S903K3B6 - 16MHz 8-Bit MCU with 8KB Flash | STMicroelectronics
Référence : STM8S903K3B6 ✓ ActifSTM8S903K3B6 Présentation
A microcontroller is a programmable integrated circuit containing a CPU core, memory, and peripherals that execute firmware and interact with external hardware. The STM8S903K3 belongs to the STM8 access-line family, which combines an 8-bit core, integrated nonvolatile data EEPROM, and mixed-signal peripherals in a relatively small package. It is intended for cost-sensitive embedded products that need more capability than a basic logic controller without adopting a higher-performance 32-bit MCU.
The STM8S903K3B6 provides 8 KB of Flash for program storage, 1 KB of RAM for working data, and 640 bytes of true EEPROM for parameter retention. Its 10-bit ADC supports analog measurements, while two timers support timing and periodic control functions. UART, SPI, and I²C provide three distinct communication paths for external sensors, actuators, displays, and serial peripherals. The 16 MHz clock enables predictable execution of control loops and interrupt-driven firmware.
STMicroelectronics describes the STM8S903K3/F3 access line as an 8-bit MCU family offering 8 Kbyte Flash program memory and integrated true data EEPROM. The target device is identified by the STM8S903K3 ordering code and B6 package/temperature suffix. The verified product information specifies a 2.95 V to 5.5 V supply range, a 16 MHz clock, and an operating lifecycle status of ACTIVE.
Typical uses include compact industrial controllers, sensor-interface modules, appliance controls, communication transceivers, low-cost instrumentation, and general-purpose embedded products. The combination of ADC, timers, EEPROM, and serial interfaces permits a single controller to acquire analog data, execute deterministic timing functions, preserve calibration values, and communicate with a host or peripheral device.
Designers should budget PCB area for the 32-pin SDIP footprint and confirm that the selected schematic uses only functions and pin assignments supported by the exact STM8S903K3 variant. Power-supply decoupling, programming access, reset behavior, and analog-input conditioning should be validated against the manufacturer datasheet before layout release. Because the search excerpts do not provide the complete pin map, a new design must not infer pin assignments from a similarly named STM8 device.
This page consolidates verified manufacturer and distributor specifications, lifecycle information, interface capabilities, and package details with selection guidance and practical design cautions. It also distinguishes confirmed same-package alternatives from candidates that require additional engineering verification, helping engineers avoid treating broadly similar MCUs as automatic drop-in replacements.
Alternatives de remplacement direct pour STM8S903K3B6 — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
STM8S903K3B3
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
STM8S103K3B3
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
STM8S103K3B6
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
STM8S903K3B6 Valeurs maximales et caractéristiques électriques
| Product Type | 8-bit microcontroller (MCU) |
| Product Family | STM8S series |
| Architecture | STM8 CISC |
| Maximum Clock Speed | 16 MHz |
| Flash Program Memory | 8 KB |
| Flash Organization | 8K x 8 bits |
| RAM | 1 KB |
| EEPROM | 640 bytes |
| ADC Resolution | 10 bits |
| I/O Ports | 16 ports |
| Timer Count | 2 timers |
| Serial Interfaces | UART, SPI, and I²C |
| Supply Voltage Range | 2.95 V to 5.5 V |
| Boîtier | 32-pin SDIP, 0.300 inch, 0.65 mm pitch |
| Style de montage | Through-hole |
| Statut du cycle de vie | ACTIVE |
| Statut RoHS | RoHS compliant |
| Reset Features | Low-consumption power-on reset and power-down reset |
Guide de configuration des broches du STM8S903K3B6 32-pin sdip, 0.300 inch, 0.65 mm pitch
Configuration des broches du STM8S903K3B6 (boîtier 32-pin sdip, 0.300 inch, 0.65 mm pitch). Ce circuit intégré numérique comprend des GPIO, des interfaces de communication (UART, SPI, I2C) et des broches d'alimentation. Consultez la fiche technique du fabricant pour les fonctions alternatives des broches et les options de configuration. Indispensable pour la conception de systèmes embarqués et la conception de circuits imprimés.
Aucune donnée de brochage détaillée disponible pour STM8S903K3B6.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
STM8S903K3B6 convient pour 6 applications: Compact Industrial Sensor Controller, Appliance and HVAC Control Panel, Serial Communication Bridge, Low-Cost Data Acquisition Module, LED Lighting and Sequencer Control, Battery-Powered Embedded Instrument.
Compact Industrial Sensor Controller
The STM8S903K3B6 fits compact industrial sensor modules because it combines a 16 MHz 8-bit core, a 10-bit ADC, 16 I/O ports, and 1 KB RAM in one 32-pin SDIP device. It can sample an analog sensor, execute timing and threshold logic, and retain calibration parameters in the 640-byte EEPROM. UART or I²C can expose measurements to a higher-level controller. The 2.95 V to 5.5 V supply range supports common industrial supply levels. Because the verified excerpts do not provide the ADC channel count or complete pin map, designers must verify channel availability, analog-reference requirements, and isolation boundaries in the official datasheet before finalizing the board.
Recommandé
Appliance and HVAC Control Panel
The STM8S903K3B6 is appropriate for appliance and HVAC user interfaces that combine button inputs, indicators, a small display interface, and periodic actuator control. Its 16 I/O ports provide a useful connection budget, while the two timers can organize display refresh, debounce timing, or motor-update intervals. The 640 bytes of true EEPROM can preserve operating modes or calibration settings, and UART or SPI can connect a display or remote interface. The 16 MHz performance supports responsive event-based firmware. Designers should budget decoupling and verify the exact pin assignments because the supplied source excerpts identify the SDIP-32 package but do not publish a complete verified pin table.
Recommandé
Serial Communication Bridge
The STM8S903K3B6 can serve as a compact protocol-conversion or acquisition bridge because it offers UART, SPI, and I²C interfaces on the same microcontroller. A firmware design can receive data over UART, translate or validate it, and forward it through SPI or I²C while using timers for timeouts and periodic reporting. Its 8 KB Flash supports a focused protocol stack, and 1 KB RAM is suitable for bounded buffering. The 2.95 V minimum operating voltage broadens compatibility with 3.3 V systems. Production validation should confirm baud-rate tolerance, peripheral pin multiplexing, interrupt behavior, and timing margins using the exact STM8S903K3 datasheet rather than another STM8 variant.
Recommandé
Low-Cost Data Acquisition Module
The STM8S903K3B6 fits a low-cost acquisition module that measures slow or moderate-rate analog signals and records operating parameters. Its 10-bit ADC is the primary analog interface, while 640 bytes of EEPROM can hold calibration coefficients or configuration records. The 1 KB RAM supports temporary samples, and two timers can establish periodic sampling intervals. UART provides a simple path for a host computer or display, while SPI or I²C can connect a sensor or external nonvolatile memory. At 16 MHz, the device is suited to deterministic low-bandwidth measurement rather than high-rate waveform acquisition. Verify ADC input count, acquisition time, input impedance, and reference limits in the manufacturer datasheet.
Recommandé
LED Lighting and Sequencer Control
The STM8S903K3B6 can implement a deterministic LED sequencer, status-light controller, or programmable indicator panel. Its two timers support periodic update intervals and duty-cycle generation, while 16 I/O ports can drive multiple channels directly or through suitable driver circuitry. SPI is useful for driving a serial display or addressable LED device, and UART permits configuration from a host. EEPROM can retain lighting scenes or user preferences. Design engineers should verify maximum GPIO drive current and alternate-function assignments from the official datasheet, since those limits were not included in the verified search excerpts. Transistor or constant-current stages may be required for LED strings rather than direct high-current drive.
Recommandé
Battery-Powered Embedded Instrument
The STM8S903K3B6 can support a compact battery-powered instrument when low cost, EEPROM retention, and mixed peripheral availability are priorities. The 2.95 V to 5.5 V operating range permits use with regulated 3.3 V or 5 V rails, and the access-line device includes power-on and power-down reset functions identified in the verified data. Firmware can use the ADC for a sensor, UART for configuration, and EEPROM for settings, then place the system into a low-power state between measurements. The exact sleep currents, wake-up timing, and analog accuracy were not supplied, so battery-life calculations and duty-cycle design require the manufacturer datasheet. A regulator selected for the load should also account for the MCU's operating current.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour STM8S903K3B6 — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | STM8S903K3B3 | STM8S103K3B3 | STM8S103K3B6 |
|---|---|---|---|---|
| Package | SDIP-32 | SDIP-32 | SDIP-32 | SDIP-32 |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Architecture | 8-bit STM8 CISC | 8-bit STM8 CISC | 8-bit STM8 CISC | 8-bit STM8 CISC |
| Maximum Clock Speed | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Flash Memory | 8 KB | 8 KB | 8 KB | 8 KB |
| RAM | 1 KB | 1 KB | 1 KB | 1 KB |
| EEPROM | 640 bytes | 640 bytes | 640 bytes | 640 bytes |
| ADC Resolution | 10 bits | 10 bits | 10 bits | 10 bits |
| Supply Voltage Range | 2.95 V to 5.5 V | 2.95 V to 5.5 V | 2.95 V to 5.5 V | 2.95 V to 5.5 V |
Principaux différenciateurs
- Directly matched STM8S903K3 family option (vs STM8S103K3B3)
- Same-package 16 MHz STM8 replacement path (vs STM8S103K3B6)
- Access-line integration without a larger memory footprint (vs STM8S105K6T3C)
Notes de conception
Reserve the 32-pin SDIP footprint on a 0.65 mm pitch and verify every signal against the exact STM8S903K3B6 pin map before PCB release. The supplied sources confirm the package and pitch but do not expose the complete numbered pin table, so do not infer assignments from STM8S103 or other STM8 devices. Preserve access to programming and reset pins, provide a clean ground reference near the MCU, and place input/output decoupling capacitors close to their corresponding pins.
Design the supply network for the verified 2.95 V to 5.5 V operating range. Confirm power-on and power-down reset behavior, startup current, and the load's dynamic demand against the manufacturer datasheet. Place stable bypass capacitance at the supply pins and isolate noisy switching circuitry from the MCU and analog reference paths. The 10-bit ADC is useful for basic measurement, but its usable accuracy depends on reference stability, source impedance, acquisition timing, and grounding rather than resolution alone.
Do not substitute the STM8S103K3U6 when the existing board uses the STM8S903K3B6's 32-pin SDIP footprint; the verified comparison identifies a TSSOP-20 package for that candidate, requiring a PCB change. Likewise, do not assume that changing between STM8S903 and STM8S103 suffixes preserves peripheral behavior. Review the register map, interrupt vectors, timer channels, ADC channels, alternate functions, and boot or programming procedure, then recompile and regression-test the firmware.
For designs using UART, SPI, or I²C, keep traces short and route them away from switching nodes and high-current LED drivers. Provide a common, low-impedance ground plane and place the MCU near the supporting sensors and interface components. If the board includes both the 10-bit ADC and communication ports, segregate analog and digital paths where practical and maintain a quiet reference area. The verified data does not provide package dimensions or exact pin locations, so obtain those from the official mechanical drawing.
Informations de conformité
The verified distributor specification identifies the STM8S903K3B6 as RoHS compliant. No verified REACH, halogen-free, lead-free, conflict-minerals, or automotive-qualification statement was supplied, so those fields remain unknown or not applicable.
