IPC Class 3
Due to the demand for high reliability while operating in extremely harsh environments, it is mandated to meet IPC Class 3 standards for defense and space industry.
Class 3 products demand continued high performance or performance-on-demand is critical, equipment downtime cannot be tolerated, end-use environment may be uncommonly harsh, and the equipment must function when required, such as life support or other critical systems. Hence, the requirements for special considerations in terms of design, fabrication and assembly.
Quality is critical where reliability is paramount. Hence, it is a pre-requisite in ensuring quality standards in electronics are applied across the production process for work carried out. Following are the IPC Class 3 standards adopted for PCB design and manufacturing,
- Printed Board Design : IPC-2220 Series/IPC-2222(Rigid)/ IPC-2223(Flex) Class 3
- Electronics Assembly Acceptance : J-STD-001/IPC-A-610 Class 3
- Solderability : J-STD-002/3 Class 3
Radiation Resilience approach
Radiation testing on space borne design pivoted on proton intensities ideal for Single Event Effects testing and Radiation Damage Determination on the components, hence incorporation of radiation hardened/tolerant components where it deem necessary.
The approach to ensuring the radiation resilience shall commence with the modelling and prediction of the space environment according to ECSS-E-ST-10-12C standard. Hence the components can be assessed on its survivability by taking reference to the parameters and results of the Proton Radiation testing and derating. The radiation test campaign shall be carried out to validate the radiation resilience of the product.
The radiation performance shall be a critical part of the space borne design as it aims to address the anticipated effects of radiation throughout the mission.
Reliability engineering consists of a battery of Modelling, Prediction and Testing activities that are aimed at quantifying, improving and demonstrating product reliability.
Reliability Modelling and Prediction shall follow the concepts laid out in MIL-STD-756 and the calculations methods and reliability figures suggested in MIL-HDBK-217 and the Telcordia SR-332 standard. Prediction shall be an iterative process vital to the design configuration and component selection activities.
Testing shall be vital in qualifying the survivability and demonstrating the mission reliability of the design. Full Qualification Tests shall be done on Engineering Models to qualify the design and accurate Acceptance Tests shall be done on Flight Models to ensure assembly and manufacturing quality. Results from the prediction activities at the early stage of the design process shall be verified via Accelerated Life Testing on representative Engineering Models. Test methodologies shall be adopted from standards and handbooks published by ECSS.
The terminal will be subjected to a comprehensive set of reliability tests. All the test parameters are based on ECSS-E-ST-10-03C standard. For EMC tests, references are taken from ECSS-E-ST-20-07 and MIL-STD-461 standards. The reliability tests for Qualification consist of random vibration, shock and thermal vacuum testing as according to MIL-STD-810 standards.