Uprating

Course Overview
Course Outline
Past Customers
Related Texts

Instructors
Contact


Course Overview

The ratings on electronic parts and selection of their use for an application environment are a matter of concern for engineers in all industries. There are standards available for derating of parts that are not application specific and often outdated. This course will discuss the part ratings, how ratings are developed, and what their implications are in selecting the use environment for parts to meet the reliability and performance requirements of the system.

Several industries, including avionics, automotive, military, and telecommunication are facing problems with obtaining electronic parts rated for the temperature range required for operation. Legacy parts rated for extended temperature ranges (e.g., military, industrial, automotive) are being discontinued by semiconductor manufacturers. In addition, more advanced and affordable functionalities (e.g., low voltage, low power) are being introduced, but only for narrower temperature ranges. To stay competitive, both technically and economically, industries may need to consider using parts whose data sheet temperature limits are not broad enough to meet the application environment. Uprating is one alternative for mitigating this problem. This course will also introduce the participants to the design, assembly, test, legal and cost issues related to uprating. Examples and case studies will be presented to illustrate each point. (This course can be customized to address electronic part derating.)

 

Course Outline

    1. The use of parts outside the manufacturer-specified temperature range

      • Changing semiconductor marketplace
      • Potential ways to meet the challenge 
      • Industry perceptions of uprating

    2. The part data sheet

      • The part number 

        • Part number conventions
      • Electronic part ratings
        • Absolute maximum ratings
        • Recommended operating conditions
        • How the ratings and conditions are determined
      • Temperatures used in ratings
        • Terminology variations
        • Examples of part temperature ranges
        • Ratings based on junction and case temperature

    3. Electrical performance specifications

      • What is specified? 
      • How are the specifications determined?
      • Specifications and temperature ratings
      • Electrical data beyond rated temperature limit
      • Electrical tests

    4. The uprating processes

      • Parameter conformance
      • Parameter re-characterization
      • Stress balancing
      • Assembly level testing

    5. The uprating methodology

      • Integrate with parts selection and management
      • Consider and evaluate alternatives
      • Obtain and accurately interpret part information
      • Determine uprating approach
      • Minimize damage from additional part handling and testing
      • Use appropriate test coverage for the application and evaluate and account for electrical parameter variabilities
      • Follow all applicable specifications, standards and known best practices
      • Determine the right margins, sample sizes, and confidence limits for your product
      • Track and evaluate changes
      • Control uprating process across supply chain
        • Keep customers informed of uprating process and instances
        • Develop and communicate appropriate maintenance information
      • Document your uprating process and results

    6. Examples of uprating successes and failures

      • Motorola MC 68332 Microcontroller
      • Fairchild 74HC244N Octal 3-State Buffer
      • Parts that could not be uprated

    7. Uprating facilities and costs

      • Selection of facilities
      • Types of facilities
      • Examples of cost

    8. Assessing and mitigating legal risks associated with uprating

      • The solution
      • U.S. product liability theories. Who's at risk?
      • U.S. measures to maximize key defenses

    9. Summary and future

      • Standardization of process technologies
      • Uprating for low temperature
      • Trends in uprating practices
      • Enhanced plastic devices
      • Upgraded parts
      • Integrated Aerospace Parts Acquisition Strategy (AQEC)
      • What are the next steps?

 

Past Customers

  • Allied Signal - Arizona
  • Emerson Electronics - Illinois
  • Ericsson and Saab - Sweden
  • Honeywell - Arizona
  • IMAPS  - Finland
  • MoD - Israel
  • Moog, Inc. Space and Defense Group
  • Raytheon -Arizona; Rhode Island

 

Related Texts

 

 

Contact

Michael Pecht
301-405-5323
education@calce.umd.edu
Bldg. 89, Rm. 1103
University of Maryland
College Park, MD 20742


 

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