This paper analyzes structural characteristics of signal vectors in combinational circuits with RTL description. Then, this paper presents the concept of the Basic Similar Circuit (BSC), a circuit constructed by compr...This paper analyzes structural characteristics of signal vectors in combinational circuits with RTL description. Then, this paper presents the concept of the Basic Similar Circuit (BSC), a circuit constructed by compressing the bit-width of vectored vectors in the original circuit. BSC shrinks the scale of the original circuit, thus improving the ATPG efficiency. Test patterns are derived from adjustment and assembling of precomputed sub-circuit test sets. Based on the deterministic algorithm, the ATPG method presented in this paper combines deterministic algorithms and undetermined methods.展开更多
In this paper,a simulation system of pseudo-random testing is described first to investigate the characteristics of pseudo-random testing.Several interesting experimental results are obtained.It is found out that init...In this paper,a simulation system of pseudo-random testing is described first to investigate the characteristics of pseudo-random testing.Several interesting experimental results are obtained.It is found out that initial states of pseudo-random sequences have little effect on fault coverage.Fixed connection between LFSR outputs and circuit inputs in which the number of LFSR stages m is less than the number of circuit inputs n leads to low fault coverage,and the fault coverage is reduced as m decreases.The local unrandomness of pseudo-random sequences is exposed clearly.Generally,when an LFSR is employed as a pseudo-random generator,there are at least as many LFSR stages as circuit inputs.However,for large circuits under test with hundreds of inputs,there are drawbacks of using an LFSR with hundreds of stages.In the paper,a new design for a pseudo-random pattern generator is proposed in which m<n.The relationship between test length and the number of LFSR stages is discussed in order to obtain necessary,fault coverage.It is shown that the design cannot only save LFSR hardware but also reduce test length without loss of fault coverage,and is easy to implement. The experimental results are provided for the 10 Benchmark Circuits to show the effectiveness of the generator.展开更多
Critical path tracing,a fault simulation method for gate-level combinational circuits,is extended to theparallel critical path tracing for functional block-level combinational circuits.If the word length of the hostco...Critical path tracing,a fault simulation method for gate-level combinational circuits,is extended to theparallel critical path tracing for functional block-level combinational circuits.If the word length of the hostcomputer is m,then the parallel critical path tracing will be approximately m times faster than the originalone.展开更多
It is known that critical path test generation method is not a complete algorithm for combinational circuits with reconvergent-fanout.In order to make it a complete algorithm,we put forward a reconvergent-fanout- orie...It is known that critical path test generation method is not a complete algorithm for combinational circuits with reconvergent-fanout.In order to make it a complete algorithm,we put forward a reconvergent-fanout- oriented technique,the principal critical path algorithm,propagating the critical value back to primary inputs along a single path,the principal critical path,and allowing multiple path sensitization if needed.Relationship among test patterns is also discussed to accelerate test generation.展开更多
This paper presents an automated POCOFAN-POFRAME algorithm thatpartitions large combinational digital VLSI circuits for pseudo exhaustive testing. In thispaper, a simulation framework and partitioning technique are pr...This paper presents an automated POCOFAN-POFRAME algorithm thatpartitions large combinational digital VLSI circuits for pseudo exhaustive testing. In thispaper, a simulation framework and partitioning technique are presented to guide VLSIcircuits to work under with fewer test vectors in order to reduce testing time and todevelop VLSI circuit designs. This framework utilizes two methods of partitioningPrimary Output Cone Fanout Partitioning (POCOFAN) and POFRAME partitioning todetermine number of test vectors in the circuit. The key role of partitioning is to identifyreconvergent fanout branch pairs and the optimal value of primary input node N andfanout F partitioning using I-PIFAN algorithm. The number of reconvergent fanout andits locations are critical for testing of VLSI circuits and design for testability. Hence, theirselection is crucial in order to optimize system performance and reliability. In the presentwork, the design constraints of the partitioned circuit considered for optimizationincludes critical path delay and test time. POCOFAN-POFRAME algorithm uses theparameters with optimal values of circuits maximum primary input cone size (N) andminimum fan-out value (F) to determine the number of test vectors, number of partitionsand its locations. The ISCAS’85 benchmark circuits have been successfully partitioned,the test results of C499 shows 45% reduction in the test vectors and the experimentalresults are compared with other partitioning methods, our algorithm makes fewer testvectors.展开更多
The atomristor(monolayer two-dimensional(2D)-material memristor)is competitive in high-speed logic computing due to its binary feature,lower energy consumption,faster switch response,and so on.Yet to date,all-atomrist...The atomristor(monolayer two-dimensional(2D)-material memristor)is competitive in high-speed logic computing due to its binary feature,lower energy consumption,faster switch response,and so on.Yet to date,all-atomristor logic gates used for logic computing have not been reported due to the poor consistency of different atomristors in performance.Here,by studying band structures and electron transport properties of MoS2 atomristor,a comprehensive memristive mechanism is obtained.Guided by the simulation results,monolayer MoS2 with moderated defect concentration has been fabricated in the experiment,which can build atomristors with high performance and good consistency.Based on this,for the first time,MoS2 all-atomristor logic gates are realized successfully.As a demonstration,a half-adder based on the logic gates and a binary neural network(BNN)based on crossbar arrays are evaluated,indicating the applicability in various logic computing circumstances.Owing to shorter transition time and lower energy consumption,all-atomristor logic gates will open many new opportunities for next-generation logic computing and data processing.展开更多
基金supported by National Natural Science Foundation of China under grant No.69733010,69973016
文摘This paper analyzes structural characteristics of signal vectors in combinational circuits with RTL description. Then, this paper presents the concept of the Basic Similar Circuit (BSC), a circuit constructed by compressing the bit-width of vectored vectors in the original circuit. BSC shrinks the scale of the original circuit, thus improving the ATPG efficiency. Test patterns are derived from adjustment and assembling of precomputed sub-circuit test sets. Based on the deterministic algorithm, the ATPG method presented in this paper combines deterministic algorithms and undetermined methods.
文摘In this paper,a simulation system of pseudo-random testing is described first to investigate the characteristics of pseudo-random testing.Several interesting experimental results are obtained.It is found out that initial states of pseudo-random sequences have little effect on fault coverage.Fixed connection between LFSR outputs and circuit inputs in which the number of LFSR stages m is less than the number of circuit inputs n leads to low fault coverage,and the fault coverage is reduced as m decreases.The local unrandomness of pseudo-random sequences is exposed clearly.Generally,when an LFSR is employed as a pseudo-random generator,there are at least as many LFSR stages as circuit inputs.However,for large circuits under test with hundreds of inputs,there are drawbacks of using an LFSR with hundreds of stages.In the paper,a new design for a pseudo-random pattern generator is proposed in which m<n.The relationship between test length and the number of LFSR stages is discussed in order to obtain necessary,fault coverage.It is shown that the design cannot only save LFSR hardware but also reduce test length without loss of fault coverage,and is easy to implement. The experimental results are provided for the 10 Benchmark Circuits to show the effectiveness of the generator.
基金The project is supported by the National Natural Science Foundation of China.
文摘Critical path tracing,a fault simulation method for gate-level combinational circuits,is extended to theparallel critical path tracing for functional block-level combinational circuits.If the word length of the hostcomputer is m,then the parallel critical path tracing will be approximately m times faster than the originalone.
文摘It is known that critical path test generation method is not a complete algorithm for combinational circuits with reconvergent-fanout.In order to make it a complete algorithm,we put forward a reconvergent-fanout- oriented technique,the principal critical path algorithm,propagating the critical value back to primary inputs along a single path,the principal critical path,and allowing multiple path sensitization if needed.Relationship among test patterns is also discussed to accelerate test generation.
文摘This paper presents an automated POCOFAN-POFRAME algorithm thatpartitions large combinational digital VLSI circuits for pseudo exhaustive testing. In thispaper, a simulation framework and partitioning technique are presented to guide VLSIcircuits to work under with fewer test vectors in order to reduce testing time and todevelop VLSI circuit designs. This framework utilizes two methods of partitioningPrimary Output Cone Fanout Partitioning (POCOFAN) and POFRAME partitioning todetermine number of test vectors in the circuit. The key role of partitioning is to identifyreconvergent fanout branch pairs and the optimal value of primary input node N andfanout F partitioning using I-PIFAN algorithm. The number of reconvergent fanout andits locations are critical for testing of VLSI circuits and design for testability. Hence, theirselection is crucial in order to optimize system performance and reliability. In the presentwork, the design constraints of the partitioned circuit considered for optimizationincludes critical path delay and test time. POCOFAN-POFRAME algorithm uses theparameters with optimal values of circuits maximum primary input cone size (N) andminimum fan-out value (F) to determine the number of test vectors, number of partitionsand its locations. The ISCAS’85 benchmark circuits have been successfully partitioned,the test results of C499 shows 45% reduction in the test vectors and the experimentalresults are compared with other partitioning methods, our algorithm makes fewer testvectors.
基金This work was supported by the National Natural Science Foundation of China(Nos.51971070,10974037,and 62205011)the National Key Research and Development Program of China(No.2016YFA0200403)+4 种基金Eu-FP7 Project(No.247644)CAS Strategy Pilot Program(No.XDA 09020300)Fundamental Research Funds for the Central Universities(No.buctrc202122)the Open Research Project of Zhejiang province Key Laboratory of Quantum Technology and Device(No.20220401)the Open Research Project of Special Display and Imaging Technology Innovation Center of Anhui Province(No.2022AJ05001).
文摘The atomristor(monolayer two-dimensional(2D)-material memristor)is competitive in high-speed logic computing due to its binary feature,lower energy consumption,faster switch response,and so on.Yet to date,all-atomristor logic gates used for logic computing have not been reported due to the poor consistency of different atomristors in performance.Here,by studying band structures and electron transport properties of MoS2 atomristor,a comprehensive memristive mechanism is obtained.Guided by the simulation results,monolayer MoS2 with moderated defect concentration has been fabricated in the experiment,which can build atomristors with high performance and good consistency.Based on this,for the first time,MoS2 all-atomristor logic gates are realized successfully.As a demonstration,a half-adder based on the logic gates and a binary neural network(BNN)based on crossbar arrays are evaluated,indicating the applicability in various logic computing circumstances.Owing to shorter transition time and lower energy consumption,all-atomristor logic gates will open many new opportunities for next-generation logic computing and data processing.