Diodes Incorporated 1N5408-B

Overview

1N5408-B from Diodes Incorporated is a 3.0A, 1000V peak repetitive reverse voltage general-purpose silicon rectifier diode in DO-201AD package, featuring 1.0V forward voltage at 3.0A, 200A non-repetitive surge capability, and low 10μA reverse leakage at 25°C - used in AC/DC power supplies, battery chargers, and DC motor control circuits.

For engineers reviewing the 1N5408-B datasheet, 1N5408-B pinout, 1N5408-B application, or 1N5408-B equivalent, key selection criteria include rated blocking voltage (1000V), thermal resistance (15°C/W), surge robustness (200A @ 8.3ms), and DO-201AD mechanical compatibility with high-current PCB layouts.

Technical Context

This axial-lead rectifier operates in single-phase, half-wave configurations with resistive or inductive loads at 60Hz; capacitive loads require 20% current derating. Its diffused junction enables stable performance across -65°C to +150°C operating range.

Thermal management relies on ambient conduction via 9.5mm lead length per spec note; typical junction-to-ambient thermal resistance is 15°C/W, and total capacitance measures 25pF at 1MHz/4V reverse bias - critical for EMI-sensitive switching inputs.

Key Specifications

Pinout & Package

Package: DO-201AD molded plastic case (UL 94V-0), axial leads with cathode band marking; weight ≈1.1 g.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar rectifier applications.

Compared with 1N5408G, the 1N5408-B offers slightly higher leakage but identical surge and thermal performance; versus RS1M, it delivers superior thermal management and mechanical robustness at the cost of larger footprint - critical for industrial power stages.

Availability

1N5408-B is available at Aetrix Electronics and suitable for AC/DC power supplies, battery chargers, and industrial control panel power inputs requiring stable component supply and long-term manufacturability.

Supply support for 1N5408-B 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, specializing in high-reliability power management and signal integrity solutions.

The S3A–S3M series, including 1N5408-B, was engineered for cost-effective, high-surge-capability rectification in legacy and maintenance-critical industrial power systems.

FAQ

Is 1N5408-B suitable for full-wave bridge configurations?

Yes - four 1N5408-B diodes can be configured as a discrete full-wave bridge rectifier. Each device handles one quadrant; ensure symmetrical PCB layout and thermal relief to maintain balanced current sharing and avoid localized overheating at 3A average load.

What is the maximum allowable ambient temperature for continuous 3.0A operation?

Per the derating curve, 3.0A average forward current is rated only at TA = 105°C when leads are held at ambient temperature at 9.5mm from the case. At 25°C ambient, the device supports ≥3.0A continuously, but actual limit depends on PCB copper area and airflow.

Does 1N5408-B have RoHS compliance documentation?

Yes - the datasheet explicitly states "Lead Free Finish, RoHS Compliant" per EU Directive Annex Notes 5 and 7, with exemptions applied for glass and high-temperature solder. Certificate of Compliance is available upon request from Diodes Incorporated.

Can 1N5408-B replace 1N5406-B in an existing design?

Yes - both share identical package, thermal specs, and surge rating; the only difference is VRRM (1000V vs. 600V). Substitution is safe if the circuit's peak reverse voltage never exceeds 600V; otherwise, 1N5408-B provides added margin against transients and aging effects.