Specifications
Manufacturer: STMicroelectronics
Device Type: Classic mainstream 32-bit Cortex-M3 embedded microcontroller, widely adopted general-purpose MCU for industrial equipment and consumer electronics
Electrical and Hardware Specifications
Processing core: ARM Cortex-M3 processor, maximum operating frequency 72 MHz
Memory allocation
Program flash memory: 512 KB
System SRAM: 64 KB
Operating supply voltage range: 2.0 V to 3.6 V
Operating ambient temperature range: -40 °C to +85 °C
Package form: 100-pin LQFP surface mount package, total 80 configurable GPIO pins
On-Chip Integrated Peripherals
Analog modules
Three independent 12-bit analog-to-digital converters, up to 21 external sampling channels, maximum conversion speed 1 MSPS
Two 12-bit digital-to-analog converters for adjustable analog voltage output
Built-in RTC real-time clock module that maintains time with backup battery power
Timing peripherals
Eight 16-bit timers including advanced control timers supporting multi-channel PWM generation and encoder signal reading
Independent watchdog and window watchdog circuits to avoid program runaway
Communication interfaces
Five USART asynchronous serial ports, three SPI buses, two I2C buses
One CAN 2.0B interface for industrial bus communication
USB full-speed device interface for data transmission and firmware upgrade
One SDIO interface compatible with SD memory cards
Auxiliary peripherals
FSMC external memory controller for driving parallel LCD, SRAM and flash chips
Multi-channel DMA controller for automatic data transmission without CPU occupancy
CRC verification unit and power supply monitoring circuit
Core Functional Characteristics
Stable and mature chip architecture with abundant verified application cases, excellent compatibility and high cost performance. The internal instruction prefetch buffer ensures smooth program execution under the rated clock frequency.
Multiple power consumption modes including running, sleep, stop and standby modes are available. Ultra-low quiescent current in standby mode extends the service life of battery-powered devices.
Part of general input and output pins support 5V voltage tolerance, equipped with internal pull-up and pull-down resistors, possessing basic anti-interference capability for conventional industrial and household electronic environments.
Complete power protection mechanisms cover power-on reset, undervoltage lockout and power-down detection, preventing abnormal program operation caused by power fluctuation.
Each chip is embedded with a unique 96-bit identification code, applied to product anti-counterfeiting, batch management and firmware authorization control.
Simple peripheral peripheral circuit requirements, fewer external auxiliary components needed, convenient for hardware design and mass production debugging.
Typical Application Scenarios
Small industrial PLC modules, frequency converter auxiliary control boards
Temperature, pressure and various environmental data acquisition terminals
Household intelligent control panels and kitchen appliance main control units
Access control systems, alarm devices and intelligent locker controllers
Handheld portable testing instruments and data loggers
Small stepper motor drive equipment and mechanical automation peripheral control modules
