STMicroelectronics L6227D

Overview

L6227D from STMicroelectronics is a DMOS dual full-bridge motor driver IC with integrated PWM current controllers, designed for bipolar stepper and dual DC motor control. It operates from 8–52 V supply, delivers 2.8 A peak (1.4 A DC) per bridge, features 0.73 Ω typical R_DS(ON) at 25 °C, supports up to 100 kHz switching, and includes non-dissipative overcurrent protection and thermal shutdown.

For engineers reviewing the L6227D datasheet, L6227D pinout, L6227D application, or L6227D equivalent, this page provides verified technical context, package-specific pin functions, real-world motor drive use cases, and validated alternative options for dual H-bridge current-controlled systems.

Technical Context

The L6227D integrates two independent BCD-technology full bridges, each with N-channel high-side and low-side DMOS transistors and intrinsic fast freewheeling diodes. Its constant t_OFF PWM current regulation uses external RC networks on RCA/RCB pins to set decay timing, with internal blanking (1 µs) preventing false triggering from diode reverse-recovery spikes.

Each bridge implements slow-decay synchronous rectification after deadtime (1 µs typ.), enabling efficient current recirculation through the upper path. Overcurrent detection is non-dissipative-sensing a precise fraction of high-side current-and pulls ENA/ENB low via an open-drain output with 4 mA sink capability when ISOVER ≥ 2.8 A is exceeded.

Key Specifications

Pinout & Package

Available in PowerSO36 (exposed slug, GND-connected) and SO24 (20 + 2 + 2 lead count) packages. Both support high-power dissipation via PCB copper planes; PowerSO36 offers lower R_th-j-case (2 °C/W) for demanding thermal environments.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual H-bridge current-controlled motor drive applications.

Compared with TB6600HG and DRV8825, the L6227D uniquely combines dual independent PWM current control, non-dissipative overcurrent protection, and 52 V operation-making it optimal for thermally constrained industrial dual-motor systems requiring robust fault handling without external sensing.

Availability

L6227D is available at Aetrix Electronics and suitable for bipolar stepper motor control, dual DC motor drive, industrial valve actuation, and automotive HVAC blower systems requiring stable component supply across extended temperature and voltage ranges.

Supply support for L6227D 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 power management, motor control, and automotive-grade ICs with broad industrial certification coverage.

The L6227D belongs to ST's "Motor Driver" product line, engineered specifically for high-efficiency, fault-resilient control of brushed DC and bipolar stepper motors in harsh environments-from factory automation to vehicle subsystems.

FAQ

What is the maximum allowable supply voltage for continuous operation?

The L6227D supports continuous operation up to 52 V supply voltage per bridge (VSA and VSB). Absolute maximum rating is 60 V, but sustained operation above 52 V risks exceeding safe operating area limits and triggering undervoltage lockout or thermal shutdown. Design margin should maintain VS ≤ 52 V under all load and temperature conditions.

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

The L6227D embeds precision current mirrors in each high-side DMOS transistor that deliver ~1/1000 of the output current to internal comparators. When sensed current exceeds 2.8 A (typ.), the comparator pulls ENA or ENB low via a 4 mA open-drain output. No external shunt is needed-power dissipation remains negligible versus conventional 0.1 Ω sense resistors dissipating >0.78 W at 2.8 A.

Can the L6227D drive unipolar stepper motors?

No-the L6227D is designed exclusively for bipolar stepper motors and dual DC motors. Its dual full-bridge topology requires four-wire (2-phase) bipolar windings. Unipolar steppers require center-tapped windings and single-polarity drive per phase, which this IC cannot support due to lack of half-bridge-only mode or center-tap switching capability.

What thermal management is required for 1.4 A DC operation in SO24 package?

At 1.4 A DC per bridge with 0.73 Ω R_DS(ON), power dissipation is ~1.46 W per bridge (2.92 W total). In SO24 on standard FR4, R_th-j-amb is 52 °C/W-resulting in ~152 °C junction rise above ambient. To stay below 125 °C max T_j, a minimum 6 cm² copper pour on bottom layer with thermal vias is mandatory, reducing R_th-j-amb to ~36 °C/W per ST's recommended layout.