Testability Method for Embedded Core-based Integrated Circuits
|Publication Date:||20 March 2005|
IEEE Std 1500 is a scalable standard architecture for enabling test reuse and integration for embedded cores and associated circuitry. It foregoes addressing analog circuits and focuses on facilitating efficient test of digital aspects of systems on chip (SoCs). IEEE Std 1500 has serial and parallel test access mechanisms (TAMs) and a rich set of instructions suitable for testing cores, SoC interconnect, and circuitry. In addition, IEEE Std 1500 defines features that enable core isolation and protection. IEEE Std 1500 will reduce test cost through improved automation, promote good design-for-test (DFT) technique, and improve test quality through improved access.
Core test language (CTL) is the official mechanism for describing IEEE 1500 wrappers and test data associated with cores. CTL is defined in IEEE P1450.6™a and was originally begun as part of the development of IEEE Std 1500.
IEEE Std 1500 was broadly influenced by the past work of the IEEE Std 1149.1™ Working Group and has several members from that group. IEEE Std 1149.1 and IEEE Std 1500 have similar goals at different levels of integration. IEEE Std 1149.1 describes a wrapper architecture and access mechanism designed for the purpose of testing components of a board whereas IEEE Std 1500 has a similar structure targeted towards testing cores in an SoC.
IEEE Std 1500 has been a continuous effort for its participants due to the goal of resolving the needs of reconciling and accommodating disparate test strategies and motives. The greatest effort has been put into supporting as many requirements as possible while still producing a cohesive and consistent standard.
Objective of the IEEE 1500 effort
The Embedded Core Test Working Group was approved in 1997 with the charter to develop a standard test method for integrated circuits (ICs) containing embedded cores, i.e., reusable megacells. That method would be independent of the underlying functionality of the IC or its individual embedded cores. The method will create the necessary testability requirements for detection and diagnosis of such ICs, while allowing for ease of interoperability of cores originated from distinct sources. This method will be usable for all classes of digital cores including hierarchical ones (subclause 15.1 discusses hierarchical core-wrapper configurations).
In order to satisfy that charter, the Embedded Core Test Working Group was organized into several task forces:
Core Test Language
Mergeable Cores Test
Industry & Media Relations
IEEE Std 1500 has developed a standard design-for-testabili