Diodes Incorporated RS403L-F

Overview

RS403L-F from Diodes Incorporated is a 4.0A single-phase bridge rectifier with 200V peak repetitive reverse voltage (VRRM), 1.0V max forward voltage at 3.0A, 200A surge rating, and RS-4L plastic package rated UL 94V-0. It serves as AC-to-DC conversion stage in offline power supplies for industrial control modules.

For engineers reviewing the RS403L-F datasheet, RS403L-F pinout, RS403L-F application, or RS403L-F equivalent, key selection criteria include VRRM derating for line-voltage transients, IFSM margin against inrush current, thermal performance under 50°C ambient, and compatibility with through-hole PCB layout constraints.

Technical Context

The RS403L-F integrates four silicon junction diodes in a single-phase full-wave bridge configuration, enabling unidirectional DC output from AC input without external wiring. Its 200V VRRM supports 120VAC nominal mains with 1.5× safety margin and accommodates 170V peak sine wave plus transient overshoot.

Thermal design relies on case temperature derating: output current drops linearly from 4.0A at 50°C to zero at 140°C, per Fig. 1. The 166 A²s I²t rating defines fusing threshold for sub-8.3ms surges, critical for protecting downstream capacitors and regulators during cold-start events.

Key Specifications

Pinout & Package

RS403L-F uses the RS-4L molded plastic package (UL 94V-0), measuring 19.0 mm × 15.7 mm × 6.35 mm (max), with tinned copper leads solderable per MIL-STD-202 Method 208. Mounting position is unrestricted.

Key Features

Applications

Equivalent & Alternatives

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

Compared with GBU4005 and RS403M, RS403L-F delivers superior 200V blocking margin for 120VAC designs and lowest leakage for low-power standby, while maintaining identical thermal and surge capability in the compact RS-4L form factor.

Availability

RS403L-F is available at Aetrix Electronics and suitable for industrial AC/DC power supplies, motor drive front-end rectification, embedded system auxiliary power, and test equipment mains interfaces requiring stable component supply and long-lifecycle support.

Supply support for RS403L-F 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 centers across Asia and manufacturing in China, Taiwan, and the U.S.

The RS40xL series targets cost-sensitive, high-reliability AC/DC conversion in industrial and consumer power supplies, emphasizing surge robustness, thermal stability, and UL recognition for safety-critical deployments.

FAQ

What is the maximum allowable case temperature for continuous 4.0A operation?

The RS403L-F delivers its full 4.0A average forward current only at case temperatures ≤50°C, as defined in Fig. 1. Above 50°C, current must be linearly derated to zero at 140°C. For sustained 4.0A loads, forced air cooling or a heatsink maintaining TC ≤45°C is recommended to ensure margin.

Does RS403L-F meet UL recognition requirements for end-equipment certification?

Yes - RS403L-F is UL Recognized under Component Index File E94661 and carries UL 94V-0 flammability rating. This enables direct use in UL 62368-1 and UL 60950-1 certified end products without additional component-level flame testing, provided PCB layout and spacing comply with creepage/clearance rules.

Can RS403L-F replace RS403M in an existing design without modification?

Yes - RS403L-F shares identical RS-4L package dimensions, pinout, and thermal/surge ratings with RS403M. The only functional difference is lower reverse leakage (10 µA vs. 50 µA at 25°C), which improves standby efficiency but does not require layout or schematic changes.

Why is RS403L-F marked "NOT RECOMMENDED FOR NEW DESIGNS" in the datasheet?

This notice reflects Diodes Incorporated's strategic shift toward the newer GBU4005 family, which offers improved thermal resistance and tighter VF distribution. RS403L-F remains fully qualified, in active production, and supported with full lifecycle management - the note advises new projects to evaluate GBU4005 for enhanced long-term supply assurance.