Worst-Case Circuit Analysis Training for Engineers by Tonex
Worst case circuit analysis (WCCA) is a cost effective means of screening a design to ensure with a high degree of confidence that potential defects and deficiencies are identified and eliminated PRIOR TO and DURING test, production and delivery.
Worst case circuit analysis is not an after-the-fact exercise but a cost-effective integral part of the design process. In fact, when engineers perform a worse case circuit analysis correctly, it can result in the savings of millions of dollars for companies as well avert potential disasters both monetary and political.
More specifically, a WCCA is a quantitative assessment of a circuit or systems functional performance, accounting for manufacturing, environmental, aging and, in the case of Space applications, radiation tolerances.
The value of an effective WCCA cannot be minimized. Through a worst case analysis many aspects of a design’s performance are computed and the risks and margins of key metrics calculated. It examines the tolerance induced effects on electronic circuits caused by potentially large and unknown magnitudes of variations of electronic piece-parts beyond their initial nominal value.
WCCA also lets engineers and organizations assess the mathematical sensitivity of circuit performance to these variations and provides both statistical and non-statistical methods for handling the variables that affect circuit performance.
These results can be valuable in helping to improve product quality and possibly salvaging 100% of a program’s cost.
The skills required to properly perform WCCA are diverse and yet each is critical to the outcome. In teaching WCCA techniques, educators often find engineers eager to tackle this critical analysis on their own, even if it is their first time.
But in reality, understanding the ins and out of worst case circuit analysis takes time. Also keep in mind that in most organizations there are multiple levels of review before an analysis is verified and complete.
WCCA is invaluable because it’s often the last line of defense against defects, recalls, hazards, and failure.
Worst-Case Circuit Analysis Training for Engineers Course by Tonex
Worst-Case Circuit Analysis Training for Engineers is 3-day short training course providing a review of worst-case circuit analysis, process, and best practices.
Participants will learn about Worst-case circuit analysis (WCCA or WCA) as a cost-effective means of screening a design to ensure with a high degree of confidence that potential defects and deficiencies are identified and eliminated prior to and during test, production, and delivery.
The course covers the details of Worst-case circuit analysis (WCCA) process and the quantitative assessment of the equipment performance, accounting for manufacturing, environmental, aging effects, etc.
This course has been produced and organized to enhance assurance processes and supporting disciplines through collaboration between industry and government across the different programs utilizing an issues-based approach. Operating conditions might include external electrical inputs, component quality level, interaction between parts, drift due to component aging and more.
Target Audience(s)
Engineers, managers, analysts, and technical leadership involved in worst-case circuit analysis. Anyone else interested in Worst-case circuit analysis as an analysis technique which, by accounting for component variability, determines the circuit performance under a worst-case scenario (under extreme environmental or operating conditions).
Learning Objectives
Upon completion of this course, the participants will be able to:
- Define terminology and key concepts and components of the worst-case circuit analysis process
- Explain the process of building design reliability into hardware for long-term field operation
- Relate to stress and de rating analysis as intended to increase reliability by providing sufficient margin compared to the allowable stress limits
- Review tools and methods of performing worst-case circuit analysis
- Analyze and determine circuit performance under extreme environmental or operating conditions
- Learn how to reduce overstress conditions that may induce failure, and reduces the rate of stress-induced parameter change over life
- Determine the maximum applied stress to each component in the system
- Apply lessons learned with demonstrations using tools, models, and simulation to accomplish worst-case circuit analysis tasks and generate a formal report
- Explain worst-case circuit analysis process and how it should be performed on all circuitry that is safety and financially critical
- Map MIL-STD-810H and environmental conditions that defined as external stresses to each circuit component. It includes temperature, humidity, or radiation
Course Agenda/Topics
Introduction to Worst-Case Circuit Analysis (WCCA)
- Executive summary
- Introduction to Worst Case Circuit Analysis (WCAA)
- Purpose of Worst Case Circuit Analysis
- General circuit analysis
- Key concepts behind Worst-Case Circuit Analysis
- Objectives of Worst-Case Circuit Analysis
Reliability Engineering 101
- Stress and derating analysis
- Failure modes and effects criticality (FMECA)
- Reliability prediction (MTBF and MTTF)
Design Verification and Reliability
- Verify the design robustness
- Operation which meets the system performance specification over design life
- Worst-case conditions and tolerances (initial, aging, radiation, temperature, etc.)
- Out-of-tolerance limits
- Degraded performance
- Circuit’s required operating limits
- Catastrophic failures
- MTBF, stress and derating, and FMECA analyses
Parts Assessment
- Part characteristics
- beginning of life analysis
- Reliability assessment
- Supports/sets critical parameters
- SCD requirements/screening definitions
- Single Event Transient (SET) analyses
Worst-case Analysis Methodology
- Analysis of a device (or system)
- Performance specifications
- Initial component tolerance
- Temperature tolerance
- Age tolerance
- Environmental exposures (such as radiation for a space device)
Worst-case Analysis Process Steps
- Generate/obtain circuit model
- Obtain correlation to validate model
- Determine sensitivity to each component parameter
- Determine component tolerances
- Calculate the variance of each component parameter as sensitivity times absolute tolerance
Relation of WCCA to Other Required Analyses
- Types of WCCA
- Unit-level vs System- or Interface-level WCCA
- Electrical Stress Analysis to verify
- Failure Modes and Effects Analysis (FMEA)
- Single Event Effects (SEE)
- Thermal analysis
- Radiation and life analysis
- Analog circuitry
- Digital circuitry
- RF and Microwave circuitry
- Power circuitry
- The Role of WCCA in System and System of Systems (SoS) Assurance
- WCCA Programmatics
- Design Heritage
- WCCA Contractual Considerations
- Personnel Requirements
- In-house versus External Analysis
- Timing of WCCA Activities
Testing Necessary for WCCA
- Environmental stress sequences, durations, and levels of equipment life cycles
- Analysis and test criteria tailored to the material and its environmental life cycle
- Material performance when exposed to a life cycle of environmental stresses
- Deficiencies, shortcomings and defects in the material design, materials, manufacturing processes, packaging techniques and maintenance methods
- Compliance with contractual requirements
- High Temperature / Low Temperature
- Humidity
- Temperature Shock
- Solar Radiation
- Rain
- Fungus
- Salt Fog Testing
- Sand and Dust Testing
- Explosive Atmosphere
- Immersion
- Acceleration
- Multi-axis acceleration testing
- Payload analysis
- Thrust application testing
- Vibration
- Shock
- Icing, Freezing Rain
Workshop 1: Creating and Working a Robust Process
- Elements of a Robust WCCA Process
- WCCA Plan
- Checklist-Driven WCCA
- Parts Data
- Environments
- Examples of common problems
- Incomplete flow of applicable requirements
- Omission of analyses and interface requirements
- Inadequate parts modeling and correlation
- Inadequate documentation of analyses or modeling/simulation
- Inadequate supporting and correlating test data
- Poor or incomplete SCDs
- Unknown or ill-defined tolerances (especially aging)
- Budget related escapes
- Schedule, cost, or contractual risk reduction
- Examples of common problems
- Schedule, Cost, or Contractual Risk Reduction
Workshop 2: Creating a WCCA Plan
- Basic Requirements
- Parts Characterization and Database
- WCCA Methodologies
- Worst-Case Conditions
- Configuration Control
- Documentation and Other Deliverables (WCCA Data Package)
- Reviews and Reviewability
- Definitions and Supplemental information
- Example WCCA Compliance Matrix (WCM)
Worse Case Circuit Analysis Training for Engineers