Fairchild Semiconductor AN9053 Assembly Guidelines for MicroFET 2x2 Packaging

About this manual

This application note details the assembly guidelines for the Fairchild MicroFET 2x2 package, a 2mm x 2mm Molded Leadless Packaging (MLP) device. It focuses on soldering and back-end processing to ensure reliable assembly and optimal thermal performance. The document addresses PWB design considerations, including pad finishes and the use of vias, as well as stencil design and solder paste selection.

What's inside

• Introduction
• Board Mounting
• PWB Design Considerations
• Pad Finish
• PWB Material
• Using Vias with MicroFET-6
• Stencil Design
• Solder Paste
• Reflow Profile
• Voiding

Specifications

Frequently asked questions

What is the recommended solder paste alloy for the MicroFET-6?

The recommended lead-free solder paste alloy is SAC 305 (96.5Sn/3.0Au/0.5Cu).

Can vias be used inside the thermal pads of the MicroFET-6?

Yes, but filled vias are preferred for high reliability applications to reduce voiding. Blind vias are not recommended.

What is the maximum recommended voiding percentage for MLP packages?

Fairchild recommends a guideline of 25% maximum voiding for MLP type packages.

Should the MicroFET-6 be reused after rework?

No, it is recommended that this component not be reused if rework becomes necessary due to high temperatures.