Technical specifications
- Manufacturer
- STMicroelectronics / module vendor
- MCU / Part
- L298N
- Architecture
- Dual bipolar H-bridge driver
- Logic voltage
- 5 V logic supply
- Recommended input
- Motor supply depends on module and cooling
- GPIO limits
- IN/EN are logic inputs; never connect motor outputs to MCU GPIO
- Flash
- N/A
- RAM
- N/A
- Clock
- PWM frequency subject to driver/module limits
- ADC
- None
- DAC
- None
- PWM / timers
- ENA/ENB accept PWM control
- Connectivity / buses
- Parallel direction and enable inputs
- Programmer
- N/A
- Debugger
- Multimeter / oscilloscope
Pin reference
| Pin | Type | Main functions | Electrical note |
|---|
| +12V/VS | Motor power | Motor supply input | Verify module rating and polarity |
| 5V/VSS | Logic power | Logic supply/output depends on jumper | Never short two 5 V sources |
| ENA/ENB | Logic/PWM | Channel enables/speed PWM | Match logic ground |
| IN1–IN4 | Logic | Direction control | Do not leave floating |
| OUT1–OUT4 | Power output | Motor terminals | Never connect to GPIO |
| GND | Power | Common return | Join MCU and motor-driver grounds |
Features and compatibility
Two DC motors, direction control, braking, stepper drive
The bipolar L298N has significant voltage drop and heat loss. Use suitable cooling, flyback protection as provided by the module, and a separate motor supply when appropriate.
Open official datasheet/documentation ↗Deep reference
Architecture, electrical limits and engineering guidance
- Exact MCU / SoC
- L298N
- Maximum GPIO current
- IN/EN are logic inputs; never connect motor outputs to MCU GPIO
- EEPROM / NVM
- Use internal data flash/NVS/flash emulation where supported; include wear levelling and power-fail protection.
- Interrupts / DMA
- GPIO/peripheral interrupts are available. DMA capability is device-specific; confirm channels, request mapping and memory-access restrictions in the reference manual.
- Sleep and power
- Use the light/deep/standby modes offered by the device. Measure board current because regulators, LEDs and USB interfaces can dominate MCU sleep current.
- Boot and programming
- Confirm boot-mode pins before reset. Use the official bootloader/programmer and retain a recoverable debug/programming header.
Special and restricted pins
Reset, clock, debug, USB, crystal and analogue-reference pins have special electrical or boot functions. Avoid loading them until the boot sequence is understood.
Boot-strapping warnings
Check BOOT/RESET/programming pin truth tables before assigning peripherals; keep required pull resistors fitted.
I/O voltage warnings
5 V logic supply domain. Never exceed VDD + permitted injection limits; level-shift incompatible modules and share ground only where safe.
Memory map and registers
Start with the memory map: code flash, SRAM, peripheral registers and system/control space. Use vendor headers instead of hard-coded addresses, then study GPIO direction/output/input, clock-enable, interrupt and timer registers.
Board-selection guidance
Choose this device only after checking logic voltage, required interfaces, memory margin, timers/ADC resolution, debugging access, package availability and long-term tool support.
Common faults and troubleshooting
Not detected: verify data USB cable, driver, boot mode and target power. Upload failure: select the exact target and programmer. Unstable operation: inspect supply ripple, reset, clock and watchdog cause. Wrong readings: check reference voltage, grounding, pin multiplexing and calibration.
Interview and viva questions
What is the difference between an absolute maximum and an operating limit?
Absolute maximum prevents damage; reliable design stays within recommended operating conditions.
Why must peripheral clocks be enabled?
Many MCUs gate clocks to save power; registers may not operate until the peripheral clock is enabled.
Why preserve a debug interface?
It enables programming, breakpoints, fault inspection and production recovery.
What causes GPIO damage?
Over-voltage, excess source/sink current, negative injection, ESD or driving against another output.
