Tin Whisker Spreadsheet

The Whisker Risk Model Spreadsheet can be used to calculate the expected number of tin whisker shorts on one or more leaded components, based on user-specified part and lead geometry, whisker density, tin whisker length distribution, applied voltage, and conformal coating coverage. The expected number of shorts is displayed numerically, as is the reliability for not shorting. In addition, graphs depicting the user-specified whisker probability density functions (PDFs), calculated whisker spacing PDFs, and calculated bridge interference PDFs are provided.

The Tin Whisker Risk Spreadsheet was developed by BAE Systems under funding from the Department of Defense's Strategic Environmental Research Program (SERDP), WP-1723. For more information please see this page.

The Spreadsheets

  • Whisker_Risk_Model_Example.xls

    A blank version of the Whisker Risk Model spreadsheet for use with the User Guide and Quick Start Guide.

  • Whisker_Risk_Model_3_6.xls

    A version of the Whisker Risk Model spreadsheet with a pre-filled Roll Up sheet. This is the spreadsheet that is described in the User Guide.

  • Geom_Whisker_Risk_Model_1_2.xls

    This is the risk model extensions for basic geometry whisker short circuit risk calculation Geom Whisker Risk Model spreadsheet. It is similar to the Whisker Risk Model spreadsheet, but models a set of simple cases: parallel flat plates, parallel round pins, and perpendicular flat plates.

User Guide

A user's manual (PDF) for the microcircuit lead whisker shorting risk calculation that provides an overview of the Whisker_Risk_Model_3_6.xls spreadsheet: what it calculates, a brief summary of the theory, a description of the individual sheets within the workbook, and two worked examples. A list of references is also included.

A user's manual (PDF) describing the risk model extensions for basic geometry whisker short circuit risk calculation Geom_Whisker_Risk_Model_1_2.xls spreadsheet is also available.

Quick Start Guide

This PowerPoint presentation provides a quick five-minute worked example to get you up and running with the spreadsheet.

Papers