STMicroelectronics L6387D

Overview

L6387D from STMicroelectronics is a high-voltage, dual-channel gate driver IC designed to independently drive N-channel power MOSFETs or IGBTs in half-bridge configurations. It features 600 V floating high-side capability, 400 mA source / 650 mA sink output current, 50/30 ns rise/fall times (1 nF load), CMOS/TTL-compatible Schmitt-trigger inputs with hysteresis, and an integrated bootstrap diode. It is used in industrial motor drives and SMPS inverters requiring robust high-side gate control.

For engineers reviewing the L6387D datasheet, L6387D pinout, L6387D application, or L6387D equivalent, key selection criteria include bootstrapped high-side rail tolerance (up to 600 V), dV/dt immunity (±50 V/ns), interlocked logic inputs to prevent shoot-through, internal UVLO thresholds (6.0 V turn-on, 5.5 V turn-off), and SO8 Minidip thermal resistance (150 °C/W).

Technical Context

The L6387D implements a level-shifted high-side driver architecture using BCD "Off-Line" process technology, enabling operation with V_OUT up to 580 V when V_BOOT − V_OUT ≥ 17 V. Its interlocked input logic (HIN/LIN truth table) enforces mutually exclusive high/low-side activation to prevent cross-conduction.

It integrates a patented synchronous bootstrap DMOS structure (R_DS(on) = 125 Ω typ.) that replaces external fast-recovery diodes, reducing leakage and board area. Charging occurs only when LVG is active and V_OUT is near GND, with timing-dependent voltage drop governed by V_drop = Q_gate × R_DS(on) / T_charge.

Key Specifications

Pinout & Package

Package: SO8 Minidip (body size 5.0 mm × 4.0 mm, lead pitch 1.27 mm, R_{th j-amb} = 150 °C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage half-bridge gate driver applications.

Compared with IR2110PbF and UCC27211D, the L6387D uniquely combines integrated bootstrap diode, hardware interlock, and 50 V/ns dV/dt immunity-reducing BOM count and improving noise resilience in cost-sensitive industrial inverters.

Availability

L6387D is available at Aetrix Electronics and suitable for industrial motor drives, AC-DC power factor correction, and uninterruptible power supplies requiring stable component supply and long-term production continuity.

Supply support for L6387D 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, analog, MEMS, and microcontrollers for industrial, automotive, and consumer markets.

The L6387D belongs to ST's high-voltage gate driver product line, engineered specifically for cost-effective, robust half-bridge control in offline AC-DC and motor drive systems operating up to 600 V.

FAQ

What is the maximum allowable V_BOOT − V_OUT differential for reliable operation?

The L6387D requires V_BOOT − V_OUT ≥ 17 V to guarantee full 580 V V_OUT swing. Below this, V_OUT is limited per the recommended operating condition note: if V_BOOT − V_OUT < 18 V, V_OUT must be clamped to ≤580 V. This ensures proper biasing of the high-side level shifter and driver stage.

Can the L6387D drive both N-channel and P-channel MOSFETs in the high-side position?

No-the L6387D is designed exclusively for N-channel high-side switches. Its floating high-side driver outputs a positive gate voltage relative to V_OUT, which is necessary to turn on N-MOS devices. It does not provide negative gate drive or level-shifting for P-MOS, and its truth table and output structure assume N-channel topology.

How does the internal bootstrap DMOS affect minimum duty cycle requirements?

The internal bootstrap DMOS requires LVG to be active while V_OUT ≈ GND to recharge C_BOOT. This mandates a minimum low-side conduction time (≥5 µs typical) per cycle. At 400 kHz (2.5 µs period), the L6387D cannot sustain >95% high-side duty cycle without external bootstrap assistance due to insufficient recharge window.

Is the L6387D pin-compatible with newer ST gate drivers like the L6387E?

No-L6387D and L6387E share identical pinout and function but differ in process and ESD rating (L6387E offers enhanced 2 kV HBM ESD). However, L6387E is not a direct drop-in replacement due to revised thermal derating and updated UVLO hysteresis; ST recommends verifying layout and timing margins before substitution.