- Posted by Juanjo Medina
- On May 7, 2020
The aim of the Declared Components List (DCL) or Declared Parts List is to provide a status list of all the EEE components intended to be used or used in a given payload or platform equipment.
The equipment supplier shall provide it, and it is used by all parties (prime contractors, product assurance companies, etc.) to make the components tracking utilized in the system. It must be understood that some elements can be changed during the different reviews of the development process and therefore, the need for a changelog as part of the DCL.
In most projects, ESCC/MIL qualified parts with no additional test and not subjected to radiation discussion are approved directly by listing them correctly in the DCL. However, the rest of the components need to be approved by the applicable Parts Approval Document (PAD) in addition to the standard listing of their values and main characteristics in the DCL.
Therefore, the great significance to configure a complete and proper DCL.
As ECSS-Q-ST-60C_rev.2 (21october2013) shows, a DCL must meet the following requirements:
- For each equipment, its supplier shall issue a DCL in an editable and sortable electronic format, as minimum compatible with “CSV” (comma-separated values), identifying all components types needed.
- The list specified in point 1 shall be kept under configuration control (issue and identification of changes).
- The DCL shall be issued as a minimum at Preliminary Design Review (PDR) and Critical design review (CDR) (as designed) and before the Test Readiness Review (TRR) (as built).
- After equipment CDR, all modifications affecting the PAD information shall be implemented, in the “as design” DCL, through the Change Notice (CN) / Change Request (CR) process and submitted to the customer for approval.
- The “as design” DCL shall be sent to the customer for approval.
- Any change of parts during equipment manufacturing (e.g. type and manufacturer) shall be handled through Request For Waivers (RFWs) submitted to the customer for approval before mounting.
- The “as-built” DCL reflecting the actual EEE parts assembled into the flight hardware and their date code, shall be provided before TRR to the customer for review.
The scope and content should include or refer to the following information. There is not just one way to conform to the DCL, so the information to be involved can slightly change, depending on project needs.
- A Description of the purpose, content and the reason prompting its preparation.
- A list of the application and reference documents.
- Any additional terms, definitions or abbreviations.
- Component number (commercial equivalent designation). A unique designation under specification used for the procurement. This component designation will describe the characteristics of the component unambiguously following generic, detail and amendment specification. E.g., 520100211R or JANSR2N2222AUBG.
- Family (ESCC group Code). Set of components with same electronic function. E.g., capacitors (01), microcircuits (08), discrete (12), resistors (10), etc.
- Die protecting enclosure allowing external connections. E.g., FP-14 or LCC-4.
- Value or range of benefits with tolerance for non-qualified parts.
- Component manufacturer (name, country).
- Generic procurement specification. An official document which describes relevant details of each family of components, terminology, test procedures, the overall sequence of a test during the manufacturing. It also defines which the manufacturer must submit documentation. It shall be noted that current ECSS-Q-ST-60C_rev.2 doesn’t mention explicitly to include the issue of generic spec for qualified parts. E.g., ESCC 5000 or MIL-PRF-19500.
- Detailed procurement specification (with issue and revision for non-qualified parts). Official document where the component technical requirements are clearly defined (electrical parameters values, mechanical features, drifts regarding the Generic Specification and additional details as test procedures, marking maximum ratings, etc.). E.g., ESCC 5201/002 or MIL-PRF-19500/255.
- Specification amendment (including issue and revision). If applicable.
- Name of the procurement agents (CPPA, supplier, distributor).
- Quality level. It defines the component reliability and will depend on the requirements for future usage and the Specifications with which are assessed. G.: QML Q, QML V, ESCC, FR R, etc.
- Lot test (ESCC LAT (Lot Acceptance Test) or LVT (Lot Validation Test), MIL QCI (Quality Conformance Inspection)). Set of tests carried out by the manufacturer over selected samples of a lot to certify the compliance of the quality requirements.
- Space qualified status (yes or no) according to the standard systems, usually ESCC, MIL/DLA, JAXA…
- RVT (yes or no). Radiation Verification Test where the electrical performance of a component can be tested after gamma-ray irradiation.
- Reference of the PAD or Justification Document (with issue and revision), where required.
- The approval status of the part. If it is suitable or not.
- Change identification between each DCL issue. During the project, different phases could occur changes in components types. In this manner, proper control can be managed.
- Date-code (only for “as-built” DCL). Alpha-numeric system used by the manufacturer for the lot traceability during its production. Generally, it is formed with 4 component digits, 2 for the year and 2 for the week, indicating the date of the manufacture. E.g., 1805 (the year 2018, 5th week).
Although it may look like an administrative document with relative low added value in terms of engineering, the Declared Part List for equipment is one of the essential documents under a permanent revision of the prime contractor and could be customized in accordance to project requirements to include additional information (SEE (Single Event Effect) data, previous reports for radiation or LAT/DPA (Destructive Physical Analysis), dependencies of items to other unit decisions….).
The consideration of Alter Technology for the design and validation of the project/unit DCL is the way to assure the successful release of this vital document, driver of the unit review process.
- Radiation Sensitive Technologies and EEE Parts - September 28, 2020
- Declared Component List. EEE Components for Space. - May 7, 2020
- Parts Approval Document (PAD). EEE components testing. - May 7, 2020