24 research outputs found
An Integrated Test Plan for an Advanced Very Large Scale Integrated Circuit Design Group
VLSI testing poses a number of problems which includes the selection of test techniques, the determination of acceptable fault coverage levels, and test vector generation. Available device test techniques are examined and compared. Design rules should be employed to assure the design is testable. Logic simulation systems and available test utilities are compared. The various methods of test vector generation are also examined. The selection criteria for test techniques are identified. A table of proposed design rules is included. Testability measurement utilities can be used to statistically predict the test generation effort. Field reject rates and fault coverage are statistically related. Acceptable field reject rates can be achieved with less than full test vector fault coverage. The methods and techniques which are examined form the basis of the recommended integrated test plan. The methods of automatic test vector generation are relatively primitive but are improving
A Retiming-Based Test Pattern Generator Design for Built-In Self Test of Data Path Architectures
Recently, a new Built-In Self Test (BIST) methodology based on balanced bistable sequential kernels has been proposed that reduces the area overhead and performance degradation associated with the conventional BILBO-oriented BIST methodology. This new methodology guarantees high fault coverage but requires special test sequences and test pattern generator (TPG) designs. In this paper, we demonstrate the use of the retiming technique in designing TPGs for balanced bistable sequential kernels. Experimental results on ISCAS benchmark circuits demonstrate the effectiveness of the designed TPGs in achieving higher fault coverage than the conventional maximal-length LFSR TPGs
A Retiming-Based Test Pattern Generator Design for Built-In Self Test of Data Path Architectures
Recently, a new Built-In Self Test (BIST) methodology based on balanced bistable sequential kernels has been proposed that reduces the area overhead and performance degradation associated with the conventional BILBO-oriented BIST methodology. This new methodology guarantees high fault coverage but requires special test sequences and test pattern generator (TPG) designs. In this paper, we demonstrate the use of the retiming technique in designing TPGs for balanced bistable sequential kernels. Experimental results on ISCAS benchmark circuits demonstrate the effectiveness of the designed TPGs in achieving higher fault coverage than the conventional maximal-length LFSR TPGs
The Telecommunications and Data Acquisition Report
Deep Space Network advanced systems, very large scale integration architecture for decoders, radar interface and control units, microwave time delays, microwave antenna holography, and a radio frequency interference survey are among the topics discussed
A unified method for assembling global test schedules
In order to make a register transfer structure testable, it is usually divided into functional blocks that can be tested independently by various test methods. The test patterns are shifted in or generated autonomously at the inputs of each block. The test responses of a block are compacted or observed at its output register. In this paper a unified method for assembling all the single tests to a global schedule is presented. It is compatible with a variety of different test methods. The described scheduling procedures reduce the overall test time and minimize the number of internal registers that have to be made directly observable
Maximizing the fault coverage in complex circuits by minimal number of signatures
Methods to minimize the number of evaluated signatures without reducing the fault coverage are presented. This is possible because the signatures can influence one another during the test execution. For a fixed test schedule a minimal subset of signatures can be selected, and for a predetermined minimal subset of signatures the test schedule can be constructed such that the fault coverage is maximum. Both approaches result in significant hardware savings when a self-test is implemented
The design of random-testable sequential circuits
A method is described for selecting a minimal set of directly accessible flip-flops. Since this problem turns out to be NP-complete, suboptimal solutions can be derived using some heuristics. An algorithm is presented to compute the corresponding weights of the patterns, which are time-dependent in some cases. The entire approach is validated with the help of examples. Only 10-40% of the flip-flops have to be integrated into a partial scan path or into a built-in self-test register to obtain nearly complete fault coverage by weighted random patterns
Generating Circuit Tests by Exploiting Designed Behavior
This thesis describes two programs for generating tests for digital circuits that exploit several kinds of expert knowledge not used by previous approaches. First, many test generation problems can be solved efficiently using operation relations, a novel representation of circuit behavior that connects internal component operations with directly executable circuit operations. Operation relations can be computed efficiently by searching traces of simulated circuit behavior. Second, experts write test programs rather than test vectors because programs are more readable and compact. Test programs can be constructed automatically by merging program fragments using expert-supplied goal-refinement rules and domain-independent planning techniques
The Automatic Synthesis of Fault Tolerant and Fault Secure VLSI Systems
This thesis investigates the design of fault tolerant and fault secure (FTFS)
systems within the framework of silicon compilation. Automatic design modification
is used to introduce FTFS characteristics into a design. A taxonomy
of FTFS techniques is introduced and is used to identify a number of features
which an "automatic design for FTFS" system should exhibit.
A silicon compilation system, Chip Churn 2 (CC2), has been implemented
and has been used to demonstrate the feasibility of automatic design of FTFS
systems. The CC2 system provides a design language, simulation facilities and
a back-end able to produce CMOS VLSI designs. A number of FTFS design
methods have been implemented within the CC2 environment; these methods
range from triple modular redundancy to concurrent parity code checking. The
FTFS design methods can be applied automatically to general designs in order
to realise them as FTFS systems.
A number of example designs are presented; these are used to illustrate
the FTFS modification techniques which have been implemented. Area results
for CMOS devices are presented; this allows the modification methods to be
compared. A number of problems arising from the methods are highlighted and
some solutions suggested