Diodes Incorporated DL4937-13

Overview

DL4937-13 from Diodes Incorporated is a 1.0A surface-mount fast recovery rectifier in MELF package, rated for 600V peak repetitive reverse voltage (VRRM), 1.2V max forward voltage at 1.0A, and 200ns reverse recovery time - used in AC/DC input stages of industrial power supplies and LED drivers requiring high-voltage blocking and low-loss rectification.

For engineers reviewing the DL4937-13 datasheet, DL4937-13 pinout, DL4937-13 application, or DL4937-13 equivalent, key selection criteria include VRRM derating for capacitive loads, thermal management at TT = 75°C, IRM leakage under 600V blocking, and compatibility with automated SMT placement on MELF carriers.

Technical Context

This device implements a single-phase, half-wave rectification topology optimized for 60Hz line-frequency operation with resistive or inductive loads. Its glass-passivated junction ensures low leakage (IRM ≤ 5.0 µA) and stable performance across -65°C to +150°C junction temperature range.

The fast recovery characteristic (trr = 200 ns) enables efficient switching in flyback snubber networks and auxiliary power rails where di/dt exceeds 50 A/µs. Total capacitance remains low (CT = 15 pF @ 1 MHz, 4V reverse bias), minimizing high-frequency noise coupling.

Key Specifications

Pinout & Package

MELF (Metal Electrode Leadless Face) cylindrical surface-mount package with cathode band marking; polarity defined by single axial band; RoHS-compliant matte tin plating; UL 94V-0 flammability rating; 0.25g mass; dimensions A=4.8–5.2mm, B=2.60–2.64mm, C=0.55mm nominal.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH1R06 and ES1J, DL4937-13 offers optimal balance of MELF manufacturability, 200ns trr for 100kHz designs, and proven thermal robustness in industrial power entry - making it preferred for automated SMT production where lead-free compliance and terminal temperature derating are mandatory.

Availability

DL4937-13 is available at Aetrix Electronics and suitable for industrial AC/DC power supplies, LED driver auxiliary rails, and isolated gate drive power supplies requiring stable component supply and RoHS-compliant MELF packaging.

Supply support for DL4937-13 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 DL493x series targets cost-sensitive, high-reliability rectification in industrial and lighting power systems - emphasizing thermal stability, low leakage, and automated assembly compatibility in MELF format.

FAQ

What is the maximum allowable reverse voltage for DL4937-13 in continuous operation?

The DL4937-13 has a peak repetitive reverse voltage (VRRM) rating of 600V. For continuous DC blocking, this value applies directly; for AC sine-wave inputs, RMS voltage must not exceed 420V (VR(RMS) = 420V), and capacitive loads require 20% current derating per datasheet Note.

Can DL4937-13 be used in place of a standard 1N4007 in SMT designs?

No - DL4937-13 uses a MELF package and is not a drop-in replacement for the axial-leaded 1N4007. It replaces through-hole rectifiers only when paired with MELF-compatible pick-and-place tooling and reflow profiles validated for cylindrical components.

Does DL4937-13 meet lead-free soldering requirements?

Yes - DL4937-13 is supplied with matte tin plating compliant with RoHS Directive 2002/95/EC (as revised March 2003), qualified for lead-free reflow up to 260°C peak temperature per JEDEC J-STD-020.

How does thermal performance change above 75°C terminal temperature?

Per Figure 2, average forward current (IO) must be linearly derated from 1.0A at TT = 75°C to zero at TT = 150°C. At 100°C terminal temperature, IO is reduced to approximately 0.67A; forced air or copper pour area is required to maintain safe junction temperature.