Yervant Zorian

Overview of the IEEE P1500 standard

Design reuse has been a key enabler to efficient ,SystemOn-Chip creation, by allowing pre-designed functions to be leveraged, thereby reducing development cycles and time to market, The test of these pre-designed blocks, often referred to as cores, is a primordial factor to successful design reuse methodologies, and must be considered by anticipation with various degrees of challenges depending on the mergeable or non-mergeable nature of the core. This paper presents the state and accomplishments of the IEEE 1500 proposal for the test of non-mergeable cores.

Fault modeling and test algorithm creation strategy for FinFET-based memories

FinFET transistors are playing an important role in modern technology that is rapidly growing. Embedded memories based on FinFET transistors lead to new defects that can require new embedded test and repair solution. To investigate FinFET-specific faults the existing models and detection techniques are not enough due to a special structure of FinFET transistors. This paper presents a new strategy for investigation of FinFET-specific faults. In addition to fault modeling, a new method is proposed for test algorithm synthesis. The proposed methodology is validated on several real FinFET-based embedded memory technologies. Moreover, new faults are identified that are specific only to FinFETs.

HD-BIST: a hierarchical framework for BIST scheduling and diagnosis in SOCs

This paper proposes HD-BIST, a complete framework to support the definition of the scheduling strategy and mechanism of the BISTed blocks of a complex system. Three different layers are presented, to define the HD-BIST approach in terms of a set of high-level BIST scheduling primitives, a communication protocol, and a possible hardware implementation, respectively.

Design for test and reliability in ultimate CMOS

This session brings together specialists from the DfT, DfY and DfR domains that will address key problems together with their solutions for the 14 nm node and beyond, dealing with extremely complex chips affected by high defect levels, unpredictable and heterogeneous timing behavior, circuit degradation over time, including extreme situations related with the ultimate CMOS nodes, where all processor nodes, routers and links of single-chip massively parallel tera-device processors could comprise timing faults (such as delay faults or clock skews); a large percentage of these parts are affected by catastrophic failures; all parts experience significant performance degradations over time; and new catastrophic failures occur at low MTBF.

A New Method for March Test Algorithm Generation and Its Application for Fault Detection in RAMs

In this paper, all linked and unlinked static and two-operation dynamic faults are considered. A classification for their description is introduced. To generate a test algorithm for detection of all the considered faults, it was shown that it is not an easy problem. For this purpose, a new structure-oriented method is developed. Based on the proposed method, an efficient test algorithm March LSD of complexity 75N is generated for the detection of the considered linked static and dynamic faults.

Generic BIST architecture for testing of content addressable memories

Minimal March test algorithms are developed for single-port binary and ternary content addressable memories (CAMs). Based on these test algorithms a built-in-self-test (BIST) architecture for testing of CAMs is proposed. It is an extension of an existing BIST architecture for testing of static random access memories (SRAMs) and read-only memories (ROMs). This generic BIST architecture additionally supports the following important CAM specific features: power buffer-zones, multicycle compare operations, half/quarter words and walking patterns.

A Robust Solution for Embedded Memory Test and Repair

This paper presents a robust solution for test and repair of embedded memories. The STAR (Self-Test and Repair) Memory System solution is developed within Synopsys Design Ware allowing users to create, integrate and verify embedded memory test and repair IP in system on chips. The key components and features of the SMS are discussed.

Symmetry Measure for Memory Test and Its Application in BIST Optimization

Programmable Built-in Self-Test (BIST) has been widely used for testing embedded memories. The main disadvantage of having programmability on BIST circuits is the size of Test Algorithm Register (TAR) that becomes very crucial in case of complex test algorithms. To optimize Programmable BIST hardware symmetric March tests are usually used in BIST engines. On the other hand, the used definitions do not reflect completely the existing symmetry in test algorithms and they also do not reflect the fact that the level of symmetry in a given test algorithm can be measured. A new method of symmetry measurement for memory test algorithms and a corresponding metric are introduced. A dependency between symmetry measure and BIST optimization range is analyzed. Optimization experiments that have been done for a number of well-known test algorithms show that the BIST hardware gain could reach 48%. However, the time overhead is negligible in comparison with the hardware gain. The experiments also show that starting from some point a monotone dependency between symmetry measure and BIST hardware area exists.

An effective solution for building memory BIST infrastructure based on fault periodicity

This paper introduces a new solution for building memory BIST infrastructure, based on rules of fault periodicity and regularity in test algorithms. It is proposed to describe all the periodicity and regularity rules in a form of a special Fault Periodicity Table (FPT) and March Test Template (MTT). FPT allows considering any large number of faults in one table and MTT allows obtaining March tests without using special tools for their generation.

A high-level EDA environment for the automatic insertion of HD-BIST structures

This paper presents a High-Level EDA environment based on the Hierarchical Distributed BIST (HD-BIST), a flexible and reusable approach to solve BIST scheduling issues in System-on-Chip applications. HD-BIST allows activating and controlling different BISTed blocks at different levels of hierarchy, with a minimum overhead in terms of area and test time. Besides the hardware layer, the authors present the HD-BIST application layer, where a simple modeling language, and a prototypical EDA tool demonstrate the effectiveness of the automation of the HD-BIST insertion in the test strategy definition of a complex System-on-Chip.