embedded processors controllers

STM8S903

Every spec below is cited to the manufacturer datasheet. Pick your exact ordering code, compare the closest alternatives, then ask the assistant what it means for your design.

00 — Overview

What the STM8S903 family does

The STM8S903K3 and STM8S903F3 are 16 MHz 8-bit microcontrollers featuring up to 8 Kbytes of Flash, 1 Kbyte of RAM, and 640 bytes of EEPROM. These devices include a 10-bit ADC, two timers, UART, SPI, and I²C interfaces operating at up to 8 Mbit/s and 400 Kbit/s respectively. The family supports 2.95 to 5.5 V operating voltage and offers up to 28 I/O pins on a 32-pin package. They are designed for applications requiring low power consumption, flexible clock control, and robust I/O design capable of handling current injection. The architecture includes a nested interrupt controller with 32 interrupts and multiple watchdog timers for system reliability.

Next step
Start building with STM8S903 → Every number above is cited straight from the datasheet — ask what they mean for your design, and the assistant answers from the same source documents.
Ordering code:
01 — Key specifications

STM8S903F3 datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current 200 µA 260 µA On; Operating mode; LSI RC osc. (128 kHz); idd(ah); Total current consumption in active halt mode at $ VDD = 5 \, V $ ST datasheet, p. 58 — Table 27: Total current consumption in active halt mode at
supply voltage range 2.95 V 5.5 V fCPU≤ 16 MHz; vdd(all modes, execution/write/erase); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
operating temperature -40 °C 125 °C Maximum power dissipation; ta; General operating conditions ST datasheet, p. 53 — Table 21: General operating conditions
clock frequency 1 MHz 4 MHz VDD = 2.95 to 5.5 V; fadc; ADC characteristics ST datasheet, p. 85 — Table 47: ADC characteristics
power dissipation 250 mW SO20W; pd; General operating conditions ST datasheet, p. 53 — Table 21: General operating conditions
cpu speed 16 MHz ST datasheet, p. 53 — Table 21: General operating conditions
program memory size 7.81 KB ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
ram size 1 kB ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
io count 16 ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
adc resolution 10 bit ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
core size 8 bit ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
rise time 35 ns Fast I/OsLoad = 50 pF; tr(10 % - 90 %); I/O static characteristics ST datasheet, p. 70 — Table 40: I/O static characteristics
fall time 300 ns tf(sda) ST datasheet, p. 84 — Table 46: I²C characteristics
data retention 20 year TRET = 55°C; tret(programand data memory); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
program erase cycles 300 kcycle 1 Mcycle TA = +125 °C; (data memory); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
02 — FAQ

STM8S903F3 frequently asked questions

What is the ADC resolution of the STM8S903F3?

The ADC resolution is 10 bit.

What is the maximum clock frequency when VDD is between 2.95 V and 5.5 V and fadc is specified for ADC characteristics?

The maximum clock frequency is 4 MHz.

What is the core size of the STM8S903F3?

The core size is 8 bit.

What is the maximum CPU speed of the STM8S903F3?

The maximum CPU speed is 16 MHz.

What is the data retention time for the STM8S903F3 Flash program memory and data EEPROM memory?

The data retention is 20 year at TRET = 55°C for program and data memory.

What is the fall time (tf(sda))?

The fall time (tf(sda)) is 300 ns.

What is the I/O count for the STM8S903F3?

The I/O count is 16.

What is the maximum operating temperature under maximum power dissipation and general operating conditions?

The maximum operating temperature is 125 °C.

What is the power dissipation for the STM8S903F3 in an SO20W package under general operating conditions?

The power dissipation is 250 mW.

What is the program erase cycle endurance for the Flash program memory and data EEPROM memory at TA = +125 °C?

The program erase cycle endurance is 1 Mcycle.

What is the program memory size of the STM8S903F3?

The program memory size is 7.81 KB.

What is the quiescent current (idd(ah)) for the STM8S903F3 in active halt mode with the LSI RC oscillator (128 kHz) at VDD = 5 V?

The quiescent current is 200 µA.

01 — Key specifications

STM8S903K3 datasheet parameters

ParameterMinTypMaxConditionsSource
quiescent current 66 µA 80 µA On; Operating mode; LSI RC osc. (128 kHz); idd(ah); Total current consumption in active halt mode at $ VDD = 3.3 \, V $ ST datasheet, p. 59 — Table 28: Total current consumption in active halt mode at
supply voltage range 2.95 V 5.5 V fCPU≤ 16 MHz; vdd(all modes, execution/write/erase); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
abs max current (abs max) 100 mA ST datasheet, p. 51 — Table 19: Current characteristics
operating temperature -40 °C 125 °C Maximum power dissipation; ta; General operating conditions ST datasheet, p. 53 — Table 21: General operating conditions
clock frequency 1 MHz 4 MHz VDD = 2.95 to 5.5 V; fadc; ADC characteristics ST datasheet, p. 85 — Table 47: ADC characteristics
power dissipation 45 mW TSSOP20; pd; General operating conditions ST datasheet, p. 53 — Table 21: General operating conditions
cpu speed 16 MHz ST datasheet, p. 53 — Table 21: General operating conditions
program memory size 7.81 KB ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
ram size 1 kB ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
io count 28 ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
adc resolution 10 bit ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
core size 8 bit ST datasheet, p. 9 — Table 1: STM8S903K3/F3 access line features
rise time 35 ns Fast I/OsLoad = 50 pF; tr(10 % - 90 %); I/O static characteristics ST datasheet, p. 70 — Table 40: I/O static characteristics
fall time 300 ns tf(sda) ST datasheet, p. 84 — Table 46: I²C characteristics
data retention 20 year TRET = 55°C; tret(programand data memory); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
program erase cycles 300 kcycle 1 Mcycle TA = +125 °C; (data memory); Flash program memory/data EEPROM memory ST datasheet, p. 69 — Table 39: Flash program memory/data EEPROM memory
load capacitance 20 pF c; HSE crystal/ceramic resonator oscillator ST datasheet, p. 66 — HSE crystal/ceramic resonator oscillator
03 — Alternatives

Closest matches to STM8S903

STM8L051F3P6 1.6× lower supply voltage range, 1.5× higher data retention, 1.2× lower abs max current
STM8S003F3 2.4× higher quiescent current, 1.8× lower rise time, 1.3× higher power dissipation
STM8S105C4 2.4× higher power dissipation, 2.4× higher quiescent current, 2.0× higher program memory size
STM32L011D3 4.0× higher core size, 2.4× lower fall time, 2.0× higher clock frequency
STM8L052C6 4.1× higher program memory size, 2.0× higher ram size, 1.6× higher power dissipation
STM8S001J3M3 3.7× lower power dissipation, 2.4× higher quiescent current, 1.9× higher operating temperature
PIC16LF1824 4.0× higher clock frequency, 3.9× lower ram size, 2.0× higher cpu speed
STM32L010F4 4.0× higher core size, 3.6× higher rise time, 2.0× higher clock frequency
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