Diodes Incorporated SBL550

Overview

SBL550 from Diodes Incorporated is a 5.0A, 50V Schottky barrier rectifier in TO-220AC package, featuring 0.55V forward voltage drop at 5.0A and 25°C, 175A non-repetitive surge capability, and 3°C/W thermal resistance junction-to-case-designed for low-voltage, high-frequency inverters and polarity protection circuits.

For engineers reviewing the SBL550 datasheet, SBL550 pinout, SBL550 application, or SBL550 equivalent, key selection criteria include its 50V DC blocking voltage, 5.0A average forward current at TC = 95°C, low VF performance, transient robustness via guard ring die construction, and TO-220AC thermal mounting compatibility.

Technical Context

The SBL550 operates as a single-element Schottky rectifier with unidirectional conduction, optimized for high-efficiency power conversion in switching topologies. Its guard ring die construction provides inherent transient protection without external components, and its low VF minimizes conduction losses in 12V–48V DC systems.

Thermal management is enabled by direct case-to-heatsink mounting (RθJC = 3°C/W), supporting sustained 5.0A operation at TC = 95°C. Junction capacitance is 500pF at 4.0V reverse bias and 1.0MHz, limiting high-frequency switching noise in flyback and synchronous rectifier applications.

Key Specifications

Pinout & Package

Package: TO-220AC - Molded plastic case with tin-plated terminals, UL 94V-0 flammability rating, and 2.3g mass. Mounting tab (Pin 1) is anode-connected and electrically active; Pin 2 is cathode.

Key Features

Applications

Availability

SBL550 is available at Aetrix Electronics and suitable for industrial motor drives, automotive body electronics, telecom power supplies, and embedded DC-DC converters requiring stable component supply despite end-of-life status.

Supply support for SBL550 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The SBL5xx series belongs to Diodes' high-current Schottky rectifier product line, engineered specifically for efficiency-critical, thermally constrained power conversion in automotive, industrial, and communications infrastructure.

FAQ

Is SBL550 still in production?

No-SBL550 is officially obsolete and discontinued per Diodes Incorporated's DS23043 Rev. 6 (August 2015). No alternate part is offered by the manufacturer. Aetrix Electronics maintains limited legacy stock for design continuity and repair programs, with full traceability and date-code documentation.

What is the maximum operating temperature for SBL550?

The SBL550 has a specified operating junction temperature range of –65°C to +150°C. At 5.0A average forward current, case temperature must not exceed 95°C to maintain reliability-achievable only with proper heatsinking due to its 3°C/W RθJC and 0.55V VF power dissipation.

Can SBL550 replace SBL545 in existing designs?

Yes-SBL550 is a direct voltage-grade upgrade from SBL545 (45V → 50V VRRM) with identical TO-220AC package, pinout, and thermal characteristics. Forward voltage remains 0.55V at 5.0A, so no layout or thermal redesign is needed; system-level reverse voltage margin improves by 5V.

Does SBL550 require derating for capacitive loads?

Yes-per datasheet note, average forward current must be derated by 20% when used with capacitive loads (e.g., bulk input filtering). At TC = 95°C, the usable IO drops from 5.0A to 4.0A to prevent thermal runaway caused by high inrush current peaks during capacitor charging.