Sherlock Automated Design Analysis™ is a software tool developed by DfR Solutions for analyzing, grading, and certifying the expected reliability of products at the circuit card assembly level. Based on the science of Physics of Failure, Sherlock predicts failure mechanism-specific failure rates over time using a combination of finite element method and material properties to capture stress values and first order analytical equations to evaluate damage evolution. The software is designed for use by design and reliability engineers and managers in the electronics industry. DfR Solutions is based in Beltsville, Maryland, USA, and was acquired by ANSYS, Inc. in May of 2019.
Approach
Users upload either a complete design package, like ODB++ or IPC-2581, or individual data packets, such as Gerber, Bill of Materials, and Pick and Place files. Sherlock incorporates stresses from a variety of environments into its physics-based prediction algorithms, including elevated temperature, thermal cycling, vibrations, mechanical shock and electrical stresses. Sherlock then performs several different types of reliability analysis and provides the useful and wear out portions of the life curve for each mechanism-component combination. The specific mechanisms that are evaluated and predicted include low-cycle solder fatigue due to thermal cycling, high-cycle solder fatigue due to vibration, solder cracking/component cracking/pad cratering due to mechanical shock or excessive flexure, lead fatigue, wire bond fatigue, via fatigue, electromigration, time dependent dielectric breakdown, hot-carrier injection, and negative bias temperature instability. Published research has indicated that the physics of failure-based predictions are highly accurate and are now used to validate other techniques. These individual life curves are then summed to provide a physics-based reliability curve for the overall product. Sherlock also provides design rule checks for board-level design and an overall reliability score. The reliability scoring, which is provided for the overall products – as well as individual scores and commentary for each area of analysis is used when physics-based quantitative predictions are not possible. The analysis is delivered both in PDF and HTML format. Depending on the types of analysis run and the data entered to create the analysis, reports can run between 20 and over 200 pages in length. The semiconductor module is in compliance with SAE ARP 6338 and is being considered as a replacement to traditional empirical reliability prediction methods in predicting the reliability of semiconductor devices. A graphical interface allows users to examine results, make iterations, and pre-perform analyses as necessary. The software does not allow the user to make permanent changes to the electronic design. This activity takes place within the original EDA or CAD software. Sherlock is compatible with Abaqus, Ansys, and Siemens NX.
Outputs
Sherlock Automated Design Analysis™ produces the following outputs:
A reliability score – benchmarks the risk of the design compared to industry best practices
Predicted performance over time – allows product teams to project the product performance over its lifecycle
