''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 Physics of failure is a technique under the practice of reliability design that leverages the knowledge and understanding of the processes and mechanisms that induce failure to predict reliability and improve product performance. Other definitions ...

, Sherlock predicts failure mechanism-specific failure rates over time using a combination of

finite element method The finite element method (FEM) is a popular method for numerically solving differential equations arising in engineering and mathematical modeling. Typical problem areas of interest include the traditional fields of structural analysis, heat ...

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 2019.

Approach

Users upload either a complete design package, like

ODB++ ODB++ is a proprietary CAD-to-CAM data exchange format used in the design and manufacture of electronic devices. Its purpose is to exchange printed circuit board design information between design and manufacturing and between design tools from ...

or IPC-2581, or individual data packets, such as Gerber,

Bill of Materials A bill of materials or product structure (sometimes bill of material, BOM or associated list) is a list of the raw materials, sub-assemblies, intermediate assemblies, sub-components, parts, and the quantities of each needed to manufacture an end ...

, 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 (random and harmonic), mechanical shock and electrical stresses (voltage, current, power). Sherlock then performs several different types of reliability analysis and provides the useful (constant failure rate) and wear out (increasing failure rate) portions of the life curve for each mechanism-component combination. The specific mechanisms that are evaluated and predicted include low-cycle

solder fatigue Solder fatigue is the mechanical degradation of solder due to deformation under cyclic loading. This can often occur at stress levels below the yield stress of solder as a result of repeated temperature fluctuations, mechanical vibrations, or mec ...

due to thermal cycling, high-cycle

due to

vibration Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic function, periodic, such as the motion of a pendulum ...

, solder cracking/component cracking/

pad cratering Pad cratering is a mechanically induced fracture in the resin between copper foil and outermost layer of fiberglass of a printed circuit board (PCB). It may be within the resin or at the resin to fiberglass interface. The pad remains connected to ...

due to

mechanical shock A mechanical or physical shock is a sudden acceleration caused, for example, by impact, drop, kick, earthquake, or explosion. Shock is a transient physical excitation. Shock describes matter subject to extreme rates of force with respect to ti ...

or excessive flexure, lead fatigue, wire bond fatigue,

via Via or VIA may refer to the following: Science and technology * MOS Technology 6522, Versatile Interface Adapter * ''Via'' (moth), a genus of moths in the family Noctuidae * Via (electronics), a through-connection * VIA Technologies, a Taiwan ...

fatigue,

electromigration Electromigration is the transport of material caused by the gradual movement of the ions in a conductor due to the momentum transfer between conducting electrons and diffusing metal atoms. The effect is important in applications where high direc ...

, time dependent dielectric breakdown,

hot-carrier injection Hot carrier injection (HCI) is a phenomenon in solid-state electronic devices where an electron or a “hole” gains sufficient kinetic energy to overcome a potential barrier necessary to break an interface state. The term "hot" refers to the e ...

, and negative bias temperature instability. Published research has indicated that the

physics of failure Physics of failure is a technique under the practice of reliability design that leverages the knowledge and understanding of the processes and mechanisms that induce failure to predict reliability and improve product performance. Other definitions ...

-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 (DRC) for board-level design (schematic and layout) 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 (MIL-HDBK-217, Telcordia SR-332,

FIDES Fides or FIDES may refer to: *Faith, trust, loyalty, or fidelity, or a religious belief * Fides (cycling team), an Italian professional cycling team in 1961 *Fides (deity), goddess of trust in Roman mythology * Fides (reliability), guide allowing ...

, and Siemens SN29500) 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 Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve co ...

. Sherlock is compatible with

Abaqus Abaqus FEA (formerly ABAQUS) is a software suite for finite element analysis and computer-aided engineering, originally released in 1978. The name and logo of this software are based on the abacus calculation tool. The Abaqus product suite consis ...

, Ansys, and

Siemens NX NX, formerly known as "unigraphics", is an advanced high-end CAD/CAM/ CAE, which has been owned since 2007 by Siemens Digital Industries Software. In 2000, Unigraphics purchased SDRC I-DEAS and began an effort to integrate aspects of both softwar ...

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 * A physical map of reliability issues –identifies the likely points of failure * A histogram – groups parts by degree of risk * Design recommendations –provide solutions to identified problems for rapid resolution Life curves

Sherlock map showing strain expected during impact across the PCBA

Version History

Sherlock Automated Design Analysis was launched in April 2011. Subsequent releases include * Version 3.0 - July 2013 * Version 3.1 - January 2014 * Version 3.2 - October 2014 * Version 4.0 - April 2015 * Version 4.1 - July 2015 * Version 4.2 - February 2016 * Version 5.0 - July 2016 * Version 5.1 - January 2017 * Version 5.2 - April 2017 * Version 5.3 - September 2017 * Version 2020R1 - January 2020 * Version 2020R2 - June 2020

Market Acceptance

A company has reported requiring suppliers use Sherlock to reduce risk and help accelerate design validation and product verification.M. Wagner and V. Nalla, Customer/Supplier Collaborative Accelerated Life Testing: Benefits and Considerations, International Applied Reliability Symposium, June 2014, Indianapolis, http://www.arsymposium.org/2014/abstracts/blue_s12.htm

References

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External links

DfR Solutions/Sherlock Automated Design Analysis
Computer-aided engineering software