STMicroelectronics L6398D

Overview

L6398D from STMicroelectronics is a high-voltage half-bridge gate driver IC for N-channel MOSFETs and IGBTs, featuring 600 V high-side rail capability, ±50 V/ns dV/dt immunity, 290 mA source / 430 mA sink drive strength, 75/35 ns rise/fall times (1 nF load), and integrated bootstrap diode. It enables robust motor control in home appliance inverters and industrial drives.

For engineers reviewing the L6398D datasheet, L6398D pinout, L6398D application, or L6398D equivalent, key selection criteria include bootstrap driver R_DS(on) (120 Ω), fixed 320 ns deadtime, interlocking logic behavior, TTL/CMOS-compatible 3.3 V–5 V inputs with hysteresis, and SO-8 thermal resistance (150 °C/W).

Technical Context

The L6398D implements a BCD™ "offline" process-based floating high-side driver with synchronous bootstrap charging via an integrated DMOS + series diode structure-replacing external fast-recovery diodes. Its interlocking function prevents simultaneous high- and low-side conduction by detecting overlapping HIN/LIN edges and enforcing tri-state output during conflict.

UVLO protection operates independently on VCC (9.5 V turn-on, 8.0 V turn-off) and bootstrap voltage VBO (9.0 V turn-on, 8.0 V turn-off), each with dedicated hysteresis (1.5 V and 1.0 V respectively). The logic section supports single-input operation when HIN and LIN are tied together, enabling simplified PWM control.

Key Specifications

Pinout & Package

Supplied in compact SO-8 package (ECOPACK® compliant), the L6398D features exposed pad thermal enhancement and standard 1.27 mm pitch footprint per JEDEC MS-012.

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 FAN7382MX, the L6398D uniquely combines integrated bootstrap diode, hardware interlocking, and fixed deadtime-reducing design risk and component count in cost-sensitive industrial motor drives.

Availability

L6398D is available at Aetrix Electronics and suitable for home appliance motor drives, industrial fan inverters, factory automation conveyors, and pump motor control requiring stable component supply across multi-year production cycles.

Supply support for L6398D 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, MCU, power, and sensor solutions for automotive, industrial, and consumer markets.

The L6398D belongs to ST's high-voltage gate driver product line, engineered specifically for robust, cost-effective motor control in AC/DC and DC/AC conversion stages up to 600 V.

FAQ

What is the maximum allowable bootstrap capacitor ESR for stable L6398D operation?

The L6398D's internal bootstrap driver has a typical R_DS(on) of 120 Ω. To limit voltage drop during charging, external C_BOOT ESR should remain below 1 Ω. At 5 µs charging time and 30 nC gate charge, ESR > 1 Ω contributes measurably to V_BOOT droop-potentially triggering VBO UVLO. Ceramic capacitors (X7R, 100 nF) meet this requirement.

Can L6398D drive SiC MOSFETs in hard-switching topologies?

L6398D supports SiC MOSFETs only in moderate-frequency (<200 kHz), non-resonant applications. Its 75 ns rise time and 430 mA sink current are sufficient for 1200 V/40 mΩ SiC devices with Q_g < 40 nC, but its ±50 V/ns dV/dt immunity falls short of SiC's typical >100 V/ns requirements-risking false turn-on without additional Miller clamping.

How does the interlocking function respond to simultaneous HIN and LIN high states?

When HIN and LIN both go high simultaneously-or their active edges overlap-the L6398D forces both HVG and LVG into high-impedance (tri-state) mode for the duration of the overlap plus 320 ns. This hardware-enforced interlock prevents shoot-through regardless of controller timing errors or propagation delays.

Is the L6398D compatible with 1.8 V logic controllers?

No. L6398D logic inputs require minimum 1.9 V for high-level recognition (V_IH = 1.9–2.25 V) and tolerate down to 0.8 V for low-level (V_IL = 0.8–1.1 V). A 1.8 V controller output may fall below V_IH min, causing unreliable high-state detection; level-shifting or a 3.3 V controller is required.