Iet Computers and Digital Techniques 

About: Iet Computers and Digital Techniques is an academic journal. The journal publishes majorly in the area(s): Field-programmable gate array & Network on a chip. It has an ISSN identifier of 1751-8601. It is also open access. Over the lifetime, 621 publication(s) have been published receiving 5198 citation(s).

Low energy single event upset/single event transient-tolerant latch for deep subMicron technologies

Abstract: Single event upsets (SEUs) and single event transients (SETs) are major reliability concerns in deep submicron technologies. As technology feature size shrinks, digital circuits are becoming more susceptible to SEUs and SETs. A novel SEU/SET-tolerant latch called feedback redundant SEU/SET-tolerant latch (FERST) is presented, where redundant feedback lines are used to mask SEUs and delay elements are used to filter SETs. Detailed SPICE simulations have been done to evaluate the proposed design and compare it with previous latch designs. The results show that the SEU tolerance of the FERST latch is almost equal to that of a TMR latch (a widely used latch which is the most reliable among the previous latches); however, the FERST latch consumes about 50% less energy and occupies 42% less area than the triple modular redundancy (TMR) latch. Furthermore, the results show that more than 90% of the injected SETs can be masked by the FERST latch if the delay size is properly selected.

A universal method for designing low-power carbon nanotube FET-based multiple-valued logic circuits

Abstract: This study presents new low-power multiple-valued logic (MVL) circuits for nanoelectronics. These carbon nanotube field effect transistor (FET) (CNTFET)-based MVL circuits are designed based on the unique characteristics of the CNTFET device such as the capability of setting the desired threshold voltages by adopting correct diameters for the nanotubes as well as the same carrier mobility for the P- and N-type devices. These characteristics make CNTFETs very suitable for designing high-performance multiple- V th circuits. The proposed MVL circuits are designed based on the conventional CMOS architecture and by utilising inherently binary gates. Moreover, each of the proposed CNTFET-based ternary circuits includes all the possible types of ternary logic, that is, negative, positive and standard, in one structure. The method proposed in this study is a universal technique for designing MVL logic circuits with any arbitrary number of logic levels, without static power dissipation. The results of the simulations, conducted using Synopsys HSPICE with 32 nm-CNTFET technology, demonstrate improvements in terms of power consumption, energy efficiency, robustness and specifically static power dissipation with respect to the other state-of-the-art ternary and quaternary circuits.

Efficient implementation of distributed routing algorithms for NoCs

Abstract: Chip multiprocessors (CMPs) are gaining momentum in the high-performance computing domain. Networks-on-chip (NoCs) are key components of CMP architectures, in that they have to deal with the communication scalability challenge while meeting tight power, area and latency constraints. 2D mesh topologies are usually preferred by designers of general purpose NoCs. However, manufacturing faults may break their regularity. Moreover, resource management frameworks may require the segmentation of the network into irregular regions. Under these conditions, efficient routing becomes a challenge. Although the use of routing tables at switches is flexible, it does not scale in terms of latency and area due to its memory requirements. Logic-based distributed routing (LBDR) is proposed as a new routing method that removes the need for routing tables at all. LBDR enables the implementation of many routing algorithms on most of the practical topologies we may find in the near future in a multi-core system. From an initial topology and routing algorithm, a set of three bits per switch/output port is computed. Evaluation results show that, by using a small logic, LBDR mimics the performance of routing algorithms when implemented with routing tables, both in regular and irregular topologies. LBDR implementation in a real NoC switch is also explored, proving its smooth integration in the architecture and its negligible hardware and performance overhead.

Binary-coded decimal digit multipliers

Abstract: With the growing popularity of decimal computer arithmetic in scientific, commercial, financial and Internet-based applications, hardware realisation of decimal arithmetic algorithms is gaining more importance. Hardware decimal arithmetic units now serve as an integral part of some recently commercialised general purpose processors, where complex decimal arithmetic operations, such as multiplication, have been realised by rather slow iterative hardware algorithms. However, with the rapid advances in very large scale integration (VLSI) technology, semi- and fully parallel hardware decimal multiplication units are expected to evolve soon. The dominant representation for decimal digits is the binary-coded decimal (BCD) encoding. The BCD-digit multiplier can serve as the key building block of a decimal multiplier, irrespective of the degree of parallelism. A BCD-digit multiplier produces a two-BCD digit product from two input BCD digits. We provide a novel design for the latter, showing some advantages in BCD multiplier implementations.

Enabling application-level performance guarantees in network-based systems on chip by applying dataflow analysis

Abstract: A growing number of applications, often with real-time requirements, are integrated on the same system on chip (SoC), in the form of hardware and software intellectual property (IP). To facilitate real-time applications, networks on chip (NoC) guarantee bounds on latency and throughput. These bounds, however, only extend to the network interfaces (NI), between the IP and the NoC. To give performance guarantees on the application level, the buffers in the NIs must be sufficiently large for the particular application. At the same time, it is imperative to minimise the size of the NI buffers, as they are major contributors to the area and power consumption of the NoC. Existing buffer-sizing methods use coarse-grained application models, based on linear traffic bounds or periodic producers and consumers, thus severely limiting their applicability. In this work, the authors propose to capture the behaviour of the NoC and the applications using a dataflow model. This enables one to verify the temporal behaviour and to compute buffer sizes using existing dataflow analysis techniques. The authors show what is required from the NoC architecture and demonstrate how to construct an NoC model, with multiple levels of detail. Using the proposed model, buffer sizes are determined for a range of SoC designs with a run time comparable to existing analytical methods, and results comparable to exhaustive simulation. For an application case study, where existing buffer-sizing methods are not applicable, the proposed model enables the verification of end-to-end temporal behaviour.