STMicroelectronics E-L6571BD

Overview

E-L6571BD from STMicroelectronics is a high-voltage half-bridge gate driver IC with integrated oscillator, designed to drive external N-channel MOSFETs and IGBTs in resonant and hard-switched topologies. It features 600 V high-side floating supply capability, programmable oscillator frequency (up to 200 kHz), 0.72 μs typical internal dead time (L6571B variant), ±50 V/ns dV/dt immunity, and 15.6 V Zener clamp on VS - used in AC-DC SMPS, fluorescent lamp ballasts, and induction heating inverters.

For engineers reviewing the E-L6571BD datasheet, E-L6571BD pinout, E-L6571BD application, or E-L6571BD equivalent, key selection criteria include bootstrap-based high-side drive architecture, dual-sink/source current capability (270 mA sink / 170 mA source), undervoltage lockout with hysteresis, oscillator timing via external R-C network, and DIP-8/SO-8 package compatibility for layout-constrained power stages.

Technical Context

The E-L6571BD implements a self-contained oscillator with frequency set by external RF and CF components, supporting both free-running and externally synchronized operation via the CF pin. Its internal logic enforces fixed dead time (0.72 μs typ.) between high- and low-side outputs to prevent shoot-through in half-bridge configurations.

It uses BCD (Bipolar-CMOS-DMOS) off-line technology for monolithic integration of high-voltage level-shifting, gate drivers, and protection circuitry. The VS pin includes a 15.6 V Zener clamp, while BOOT and OUT pins sustain up to 618 V and ±50 V/ns slew rates - enabling direct interface with 600 V-class power switches without external level shifters.

Key Specifications

Pinout & Package

Package: SO-8 (small-outline integrated circuit, 150 °C/W junction-to-ambient thermal resistance). Pinout validated per STMicroelectronics Doc ID 4946 Rev 6, Figure 2 and Table 4.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IR2153 and UCC27712, E-L6571BD uniquely integrates oscillator, Zener-clamped VS, and fixed dead time in SO-8 - offering lowest component count for cost-sensitive 20–100 kHz half-bridge systems without external timing or level-shifting.

Availability

E-L6571BD is available at Aetrix Electronics and suitable for AC-DC resonant SMPS, induction heating inverters, compact fluorescent lamp ballasts, and plasma ignition drivers requiring stable component supply and long-term production continuity.

Supply support for E-L6571BD 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 microcontrollers, power ICs, sensors, and automotive-grade components since 1987.

E-L6571BD belongs to ST's high-voltage analog & power IC portfolio, developed specifically for cost-optimized, self-oscillating half-bridge drivers in lighting, appliance, and industrial power conversion applications.

FAQ

What is the maximum recommended operating frequency for E-L6571BD?

The datasheet specifies a maximum oscillation frequency of 200 kHz under recommended operating conditions. At 60 kHz (typical for CFL ballasts), it delivers stable dead time and full drive capability. Operation above 100 kHz requires careful PCB layout to minimize parasitic inductance on BOOT and OUT paths, and verification of gate charge delivery against MOSFET Qg.

Can E-L6571BD drive IGBTs directly?

Yes - its 270 mA sink and 170 mA source output currents are sufficient to drive standard 15–30 A IGBTs with gate charge ≤ 100 nC at 20–50 kHz. For faster switching or higher-current IGBTs, external gate resistors must be selected to limit peak current and manage Miller plateau crossing without oscillation.

How does the CF pin function in shutdown mode?

Pulling CF to GND forces the low-side driver ON and high-side OFF, halting bridge switching while maintaining bootstrap capacitor charge. This is not a latch - release returns to normal oscillator operation. Minimum discharge pulse width must exceed 1 μs to avoid metastability, enforced by adding series resistance (R × C ≥ 1 μs) in the CF discharge path.

Is E-L6571BD pin-compatible with L6571AD?

Yes - both L6571AD (A-version, 1.25 μs dead time) and L6571BD (B-version, 0.72 μs dead time) share identical SO-8 pinout, electrical interface, and functional block diagram. Substitution requires only validation of dead time impact on ZVS margin and thermal performance in the target application.