Worst Case Analysis
 

Do You Need Worst Case Circuit Analysis? Edge consulting and sales represents AEI systems. Have a question? As WCCA experts, we are here to help.

There is no charge for initial consultations.

We are happy to discuss radiation, part tolerance, mission life, space, specification, reliability, failure, and SDRL related questions along with any other project requirements.

A Worst Case Circuit Analysis is a quantitative assessment of the equipment performance, accounting for manufacturing, environmental and aging effects. In addition to a circuit analysis, a WCCA often includes stress and derating analysis, Failure Modes and Effects Criticality (FMECA) and Reliability Prediction (MTBF).

The specific objective is to verify that the design is robust enough to provide operation which meets the system performance specification over design life under worst case conditions and tolerances (initial, aging, radiation, temperature, etc.).

The Stress and Derating Analysis is intended to increase reliability by providing sufficient margin compared to the allowable stress limits. This reduces overstress conditions that may induce failure, and reduces the rate of stress-induced parameter change over life. It determines the maximum applied stress to each component in the system.

Factors Addressed During WCCA

Analog Circuit Analysis
Some of the factors to be considered during analysis include:

  • Maximum line voltage variations and line transient.
  • Maximum input and output variation.
  • Maximum part parameter variation.
  • Maximum performance demands and variations.
  • Maximum and minimum environmental conditions.
  • Fail-safe provisions.
  • Redundancy provisions.
  • Radiation effects, as applicable.
  • Parameter drift due to aging.
  • Transients due to turn-on, turn-off, and state changes.
  • Fatigue due to cyclical loading and temperature cycling.
  • Interface conditions between modules and modules to test equipment.

Digital Circuit Analysis
Digital circuit worst case analyses involves one or more of the following:

  • Timing Margin Analysis.
  • Transmission Line Effect.
  • Noise Due to Crosstalk and Grounding.
  • Meta-Stability Analysis.
  • Decoupling Analysis.
  • Fanout Analysis.
  • Logic Compatibility/Interface Analysis.
  • Supply Power Application and Sequencing Analysis.
  • State Machine Analysis.
  • Unused/Tri-stated Input Analysis.
  • No Connection Analysis.
  • Test Point Current Limiter Analysis.
  • Physical Layout Analysis.
  • One-Shot Margin Analysis

Component Tolerances

  • Initial.
  • Temperature and Environmental Factors.
  • Radiation.
  • Aging or End-of-Life Factors.

A Partial List of AEi Systems Clients

  • Aeroflex
  • Allied Signal
  • Boeing Space
  • Brookhaven National Labs
  • Hamilton Standard
  • Hughes Space and Communications
  • International Rectifier
  • Interpoint
  • ITT Industries
  • Lockheed Martin Astronautics
  • Lockheed Sanders
  • Lucix
  • Omnirel
  • Raytheon
  • Sierra Microwave
  • Signal Technology
  • Smith-Nephew
  • Space Systems Loral
  • Starsys/SpaceDev
  • TRW Space and Technology
  • Watkins Johnson