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Assurance Process for Complex Electronics
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Life Cycle

Requirements Phase

Requirements Phase

This Overview page for the Requirements Phase contains the following sections:


This assurance plan for complex electronics assumes that the system requirements have been developed, assessed, and baselined (formalized). The system requirements should have been provided to individual components of the system, and decomposed sufficiently so that the component requirements provide sufficient detail for the designers to know what they need to create.

The engineering group creates the requirements and the assurance group verifies and validates the requirements. Both sides require a thorough knowledge of the system, including the environment where the system will operate and the expected operational scenarios. The two groups need to work closely together in the process of creating and verifying the requirements. The diagram below shows the requirements process for complex electronics. The Develop Requirements page describes the engineering process to create the requirements. The Assurance Process page describes the activities to assess and verify the requirements.

A general summary of requirements engineering is provided in the Requirements Engineering page.

Requirements Process:

Entrance Criteria:

The following criteria should be met prior to beginning the development and assurance of requirements for complex electronics.

  • The system requirements should be complete and baselined. In reality, the requirements must be sufficiently complete to allow derivation of requirements for sub-systems and the complex electronics.
  • Sub-system requirements for the sub-system(s) the complex electronics reside in should be complete and baselined. As with the system requirements, the level of fidelity must be sufficient to allow derivation of the complex electronics requirements to commence.
  • The Configuration Management process is defined and in operation.
  • The Assurance process is defined and operational. The assurance engineers responsible for the complex electronics have been identified.
  • The proposed technology set (e.g., FPGA, ASIC, SoC, chip family) is identified at a high level.

Exit Criteria:

At the end of the requirements development phase, the following criteria should be met:

  • Requirements for complex electronics are baselined and under configuration control.

Roles and Responsibilities

The table below describes typical activities during the Requirements Phase for both engineers and assurance personnel.

Requirements Phase


Typical Activities

Systems Engineer

Decompose system requirements to sub-systems and components. They may delegate this task to electronics engineers for the complex electronics requirements.

Electronics Designer

Help the systems engineer in the process of creating requirements for complex electronics. Assess the requirements for design impacts.

CE specialist (optional)

Either helps develop the requirements for complex electronics, or assess the requirements for designability with the chosen technology. Any problems should be worked out with the systems engineer. Select tools for design, implementation, and test activities.

System Safety

Perform Preliminary Hazard Analysis to identify system hazards, and the system components that contribute to the hazard, or help prevent it from occurring. If complex electronic devices are involved, include design-related failures as well as hardware failures in the analysis.

Quality Assurance

Assess the complex electronics requirements. Verify that all requirements are testable (or otherwise verifiable). Ensure that all CE requirements trace back to system, safety, or other higher-level requirements.

CE Process Assurance (new category)

Assess the complex electronics requirements against knowledge of the technology and design process. Verify that the requirements are attainable. Assess the verification activities that will be required, and ensure that the device can be verified to the level required. Assess any tools that will be used to design, implement, and test the CE.

Requirements Site Map

The table below describes the information contained on the other pages in the Requirements section.

Requirements Site Map

Overview This page

Develop Requirements

The process of developing requirements for complex electronics. This section includes a listing of requirements that should be considered for complex electronic devices.

Because complex electronics may not have a sufficiently detailed requirements specification, assurance engineers may have to derive an appropriate set of requirements in order to complete future assurance tasks.

Assurance Process

Describes the assurance process for complex electronics requirements, with links to specific techniques.

Requirements Engineering

Requirements engineering summary, including:

  • Levels of requirements
  • Types of requirements
  • Requirements derivation
  • Qualities of good requirements
  • Requirements flow down
  • Sources of requirements for complex electronics
  • Traceability of the requirements to higher level requirements, and into the design and verification process.

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Last Updated: 01/28/2008