DO-213AB (MELF) Package Overview

The DO-213AB, part of the MELF(Metal Electrode Leadless Face) package family, is a standardized,    cylindrical, leadless surface-mount device (SMD) package. It is a mature    and widely recognized industry workhorse, particularly valued for its    excellent electrical performance and long-term reliability in demanding    applications.

The package features a small, barrel-shaped glass or ceramic body with    metallic end caps that serve as terminals. It is a 2-pin device, and its    effective “pitch” is the body length. The metallic end caps are soldered    directly to the PCB pads. Engineers choose DO-213AB for its superior    high-frequency characteristics, stable parameters, robust power handling,    and proven long-term stability compared with many chip-style components.

Key Features

  • Package type: Leadless cylindrical MELF / SMD
  • Body material: Glass or ceramic
  • Terminals: Metallic end caps, 2 pins
  • Typical body size: approx. 5.2 mm × 2.2–2.67 mm
  • Typical power rating: 1.0 W
  • Mounting: Surface mount, end caps soldered to PCB pads

Typical Components

Common devices housed in DO-213AB packages include diodes such as Schottky,    Zener, switching, rectifier, fast-recovery, and TVS diodes, as well as MELF    resistors and some inductors.

Applications

  • Power supplies and power conversion
  • Automotive electronics
  • Telecommunications infrastructure
  • Precision instrumentation
  • Industrial control and high-reliability systems

PCB Layout & Assembly Notes

  • Match pad dimensions to the component datasheet to prevent tombstoning during reflow soldering.
  • Use properly shaped, elongated pads for reliable end-cap wetting.
  • Optimize the reflow profile to ensure both terminals heat evenly.
  • Automated placement usually requires a dedicated MELF nozzle or high-vacuum flat nozzle.
  • Handling can be more challenging than flat chip packages because the cylindrical body may roll.

Comparison with SOD-123

Compared with the similar SOD-123 plastic package, the DO-213AB MELF    typically offers better thermal and electrical performance, but it can be    slightly more challenging for automated placement and requires careful pad    design.