Design for testability(DFT) in VLSI is to reduce the time and effort necessary to generate test vector sequences for testing VLSI chips after fabrication. If the chips are designed for testability, identifying problematic chips after fabrication can be substantially simplified. When determining the DFT techniques to utilise for a given design , the benefits of simpler test vector generation, improved fault coverage, and possibly shorter test application time must be weighed against the drawbacks. There is no one-size-fits-all Design For Testability in the VLSI approach.
Types of testing in Design for testability:
Ad-hoc Testing
Making nodes more accessible by physically introducing more access points into the original design is one technique to improve testability. Primarily, there are certain rules which have been collected gradually after encountering various errors. The advantages of using this technique for design for testability in VLSI is that the test vector generation is interpreted, it is simple to perform and there are no design rules or constraints. However, there are certain drawbacks such as each design having its specific requirements and testability problems it is not always reusable. It also does not ensure high testability levels
Also Read: Job Prospects in ASIC Design Verification
Structured testing
Using this method for design for testability in VLSI, extra logic and signals are added to the circuit to allow the circuit to be tested according to a preset protocol. In contrast to Ad-hoc, the structured technique has its advantages, design for testability in VLSI indicates that, regardless of the circuit function, the same design methodology may always be utilised to ensure good testability levels. This strategy is widely used to solve design for testability in VLSI problems in today’s environment. However, there is a disadvantage which usually entails accepting that specific design rules are followed, as well as the increase in silicon area and propagation delays.
Conclusion
Design for testability (DFT) in VLSI training will assist a student with inside and out information on all testability strategies. DFT approaches try to reduce the time and effort necessary to generate test vector sequences for VLSI circuits.There are many VLSI training institutes that provide online VLSI courses. Chipedge, a leading VLSI training institute provides all the necessary courses for you to kickstart your career.
ChipEdge offers several VLSI courses online such as ASIC Design Verification Course, Physical Design Course for better opportunities in VLSI Jobs along with placement assistance for leading semiconductor companies in India. Get in touch with experts at Chipedge to get more details.