STMicroelectronics L6225D

Overview

L6225D from STMicroelectronics is a DMOS dual full-bridge motor driver IC designed for bipolar stepper and dual/quad DC motor control, featuring 8–52 V operating supply voltage, 2.8 A peak output current (1.4 A DC), 0.73 Ω typical R_DS(ON) per switch at T_j = 25 °C, non-dissipative overcurrent protection, and integrated fast freewheeling diodes. It operates up to 100 kHz and supports paralleled operation for higher current or lower R_DS(ON).

For engineers reviewing the L6225D datasheet, L6225D pinout, L6225D application, or L6225D equivalent, this device is selected for precision bidirectional motor drive where thermal shutdown, cross-conduction protection, bootstrap gate drive, and embedded current sensing without external shunts are required.

Technical Context

The L6225D integrates two independent full H-bridges using MultiPower-BCD technology, combining isolated DMOS power transistors with CMOS/bipolar logic on one die. Each bridge features dead-time-controlled gate drivers (1 µs typical) and internal charge-pump circuitry (V_CP = 600 kHz square wave, 10 V amplitude) to drive high-side N-channel MOSFETs.

Overcurrent detection is implemented via on-die current-sensing cells in each high-side DMOS, delivering a precise fraction of load current to an internal comparator referenced to 2.8 A threshold. Thermal shutdown activates at 165 °C (15 °C hysteresis), and ENA/ENB pins serve dual roles as enable inputs and open-drain fault outputs tied to internal protection transistors.

Key Specifications

Pinout & Package

Available in SO20 (16+2+2) package with exposed slug internally connected to pins 1, 10, 11, and 20 (GND). Thermal resistance: R_th-j-amb = 52 °C/W (standard FR4, 6 cm² top copper) or 16 °C/W (multi-layer board with vias + ground plane).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TB6612FNG and DRV8876PWPR, the L6225D uniquely combines 52 V operation, non-dissipative OCP, and flexible paralleling - making it optimal for industrial stepper and high-voltage DC motor systems where reliability, simplicity, and thermal robustness are prioritized over digital control interfaces.

Availability

L6225D is available at Aetrix Electronics and suitable for industrial motor control, automated machinery, and precision motion systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for L6225D 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, designing and manufacturing analog, MEMS, power, and microcontroller products for automotive, industrial, and consumer markets.

The L6225D belongs to ST's Power Switches & Motor Drivers product line, engineered specifically for robust, high-efficiency motor control in harsh industrial environments with emphasis on thermal resilience, integrated protection, and simplified system design.

FAQ

What is the recommended external charge-pump component set for L6225D?

The official reference design specifies C_BOOT = 220 nF, C_P = 10 nF, R_P = 100 Ω, and diodes D₁/D₂ = 1N4148. These values ensure reliable V_BOOT generation up to 100 kHz switching with minimal ripple. Ceramic capacitors are mandatory for stability; X7R or better dielectric is required. Layout must minimize loop area between V_CP, C_P, and D₁/D₂ to prevent EMI-induced bootstrap failure.

How does the non-dissipative overcurrent protection work without a sense resistor?

The L6225D embeds precision current-mirror cells within each high-side DMOS transistor that deliver ~1/1000 of the load current to internal comparators. This fractional current is compared against a stable 2.8 A-equivalent reference, triggering ENA/ENB pull-down when exceeded. No external resistor is needed because sensing occurs intrinsically in the silicon, eliminating power loss, calibration drift, and PCB footprint.

Can L6225D drive unipolar stepper motors?

No - the L6225D is designed exclusively for bipolar stepper motors and dual/quad DC motors. Its dual full-bridge topology provides four quadrant control (±V, ±I) required for bipolar phase winding excitation. Unipolar steppers require center-tapped windings and single-ended switching, which this IC does not support. Attempting unipolar use would result in incorrect current paths and potential device damage.

What is the minimum copper area required for safe operation at 1.4 A RMS per bridge?

For SO20 package at 1.4 A RMS per bridge (2.8 A total load), a minimum 6 cm² top-side copper pour (35 µm thick) reduces R_th-j-amb to 52 °C/W, limiting junction temperature rise to ~73 °C at 25 °C ambient - well below the 125 °C max rating. Adding 16 thermal vias to an internal ground plane further lowers R_th-j-amb to 16 °C/W, enabling full 2.8 A peak operation even at 70 °C ambient.