STMicroelectronics L298N

Overview

L298N from STMicroelectronics is a high-voltage, high-current dual full-bridge driver IC designed for bidirectional control of DC and bipolar stepper motors. It supports up to 46 V supply voltage, delivers up to 4 A total DC current (2 A per channel), features low saturation voltage (1.8 V typ. at 1 A), includes overtemperature protection, and accepts standard TTL logic inputs with high noise immunity (input low up to 1.5 V). It is commonly used in robotics motor controllers and CNC motion systems.

For engineers reviewing the L298N datasheet, L298N pinout, L298N application, or L298N equivalent, key selection considerations include its dual H-bridge architecture, independent enable inputs (Enable A/B), integrated current sensing terminals (Sense A/B), and thermal performance limitations requiring heatsinking above ~1 A/channel continuous operation.

Technical Context

The L298N implements two independent, TTL-compatible H-bridge output stages-each with complementary NPN/PNP Darlington transistor pairs-enabling four-quadrant control (forward/reverse/brake/coast) of inductive loads. Its input stage decodes logic-level signals (Input 1–4, Enable A/B) to drive internal gate logic that controls upper and lower transistors per bridge.

Current sensing is implemented via dedicated Sense A and Sense B pins connected to external low-value resistors (e.g., 0.5 Ω), allowing real-time load current monitoring and overcurrent shutdown when paired with external comparators or microcontroller ADCs. The separate VSS (logic supply) and VS (power supply) rails isolate logic integrity from power-stage noise and voltage drop.

Key Specifications

Pinout & Package

The L298N is available in Multiwatt15L V (15-pin vertical package with integral heatsink tab) and PowerSO-20 (20-pin surface-mount package with exposed thermal slug). Both packages feature GND-connected metal tabs for thermal management and mechanical mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual H-bridge driver applications.

Compared with L298N, STK672-430 offers built-in current regulation but less logic-level versatility, while TB6612FNG delivers superior efficiency and smaller footprint at the cost of voltage and current capability-making L298N the only choice for 24–46 V, >2 A/channel industrial motor control.

Availability

L298N is available at Aetrix Electronics and suitable for robotics motor controllers, CNC motion systems, and automated gate actuators requiring stable component supply across prototyping, pilot production, and long-lifecycle industrial deployments.

Supply support for L298N 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, specializing in automotive, industrial, and power management solutions with broad analog, digital, and mixed-signal product portfolios.

The L298N belongs to ST's legacy power driver IC family, engineered specifically for rugged, cost-effective motor control in industrial automation, robotics, and motion systems where reliability under high-voltage inductive loads is critical.

FAQ

What is the maximum continuous current per channel for L298N?

The L298N supports 2 A DC current per channel under proper thermal conditions-defined with case temperature ≤75 °C and adequate heatsinking. Without active cooling, sustained current must be reduced to ~1 A to avoid thermal shutdown. Peak current capability is 3 A (non-repetitive, 100 ms) or 2.5 A (repetitive, 80% duty cycle).

Can L298N drive a unipolar stepper motor?

No, the L298N is designed exclusively for bipolar stepper motors or dual DC motors. Its dual full-bridge topology requires four-wire (or six-wire with center taps unused) bipolar configurations. Unipolar steppers require phase-enable logic and center-tap connections incompatible with L298N's output structure.

Why does L298N have separate VS and VSS pins?

VS powers the high-current Darlington output transistors (up to 46 V), while VSS supplies the TTL-compatible input logic (4.5–7 V). This separation prevents logic voltage droop and noise coupling during high di/dt switching events, ensuring reliable signal integrity and eliminating need for external level shifters in 5 V MCU systems.

How should the Sense A and Sense B pins be used for overcurrent protection?

Connect a precision low-value resistor (e.g., 0.5 Ω) between Sense A and GND. When load current exceeds threshold (e.g., 2 A → 1 V across resistor), feed this voltage into a comparator or MCU ADC. Assert Enable A/B low upon threshold breach to disable the bridge-leveraging the L298N's fast enable propagation delay (<3 μs) for responsive fault response.