4,999 research outputs found
A Multiproject Chip Approach to the Teaching of Analog MOS LSI and VLSI
Multiproject chip implementation has been used in teaching analog MOS circuit design. After having worked with computer simulation and layout aids in homework problems, students designed novel circuits including several high
performance op amps, an A/D converter, a switched capacitor filter, a 1 K dynamic RAM, and a variety of less conventional MOS circuits such as a VII converter, an AC/DC converter, an AM radio receiver, a digitally-controlled
analog signal processor, and on-chip circuitry for measuring transistor capacitances. These circuits were laid out as part of an NMOS multiproject chip. Several of the designs exhibit a considerable degree of innovation;
fabrication pending, computer simulation shows that some may be pushing the state of the art. Several designs are of interest to digital designers; in fact, the course has provided knowledge and technique needed for detailed
digital circuit design at the gate level
An Energy and Performance Exploration of Network-on-Chip Architectures
In this paper, we explore the designs of a circuit-switched router, a wormhole router, a quality-of-service (QoS) supporting virtual channel router and a speculative virtual channel router and accurately evaluate the energy-performance tradeoffs they offer. Power results from the designs placed and routed in a 90-nm CMOS process show that all the architectures dissipate significant idle state power. The additional energy required to route a packet through the router is then shown to be dominated by the data path. This leads to the key result that, if this trend continues, the use of more elaborate control can be justified and will not be immediately limited by the energy budget. A performance analysis also shows that dynamic resource allocation leads to the lowest network latencies, while static allocation may be used to meet QoS goals. Combining the power and performance figures then allows an energy-latency product to be calculated to judge the efficiency of each of the networks. The speculative virtual channel router was shown to have a very similar efficiency to the wormhole router, while providing a better performance, supporting its use for general purpose designs. Finally, area metrics are also presented to allow a comparison of implementation costs
Recommended from our members
Automatic synthesis of analog layout : a survey
A review of recent research in the automatic synthesis of physical geometry for analog integrated circuits is presented. On introduction, an explanation of the difficulties involved in analog layout as opposed to digital layout is covered. Review of the literature then follows. Emphasis is placed on the exposition of general methods for addressing problems specific to analog layout, with the details of specific systems only being given when they surve to illustrate these methods well. The conclusion discusses problems remaining and offers a prediction as to how technology will evolve to solve them. It is argued that although progress has been and will continue to be made in the automation of analog IC layout, due to fundamental differences in the nature of analog IC design as opposed to digital design, it should not be expected that the level of automation of the former will reach that of the latter any time soon
The Rolf of Test Chips in Coordinating Logic and Circuit Design and Layout Aids for VLSI
This paper emphasizes the need for multipurpose test chips and comprehensive procedures for use in supplying accurate input data to both logic and circuit simulators and chip layout aids. It is shown that the location of test structures within test chips is critical in obtaining representative data, because geometrical distortions introduced during the photomasking process can lead to
significant intrachip parameter variations. In order to transfer test chip designs quickly, accurately, and economically, a commonly accepted portable chip layout notation and commonly accepted parametric tester language are needed. In order to measure test chips more accurately and more rapidly, parametric testers with improved architecture need to be developed in conjunction with
innovative test structures with on-chip signal conditioning
Product assurance technology for custom LSI/VLSI electronics
The technology for obtaining custom integrated circuits from CMOS-bulk silicon foundries using a universal set of layout rules is presented. The technical efforts were guided by the requirement to develop a 3 micron CMOS test chip for the Combined Release and Radiation Effects Satellite (CRRES). This chip contains both analog and digital circuits. The development employed all the elements required to obtain custom circuits from silicon foundries, including circuit design, foundry interfacing, circuit test, and circuit qualification
Improving practical sensitivity of energy optimized wake-up receivers: proof of concept in 65nm CMOS
We present a high performance low-power digital base-band architecture,
specially designed for an energy optimized duty-cycled wake-up receiver scheme.
Based on a careful wake-up beacon design, a structured wake-up beacon detection
technique leads to an architecture that compensates for the implementation loss
of a low-power wake-up receiver front-end at low energy and area costs. Design
parameters are selected by energy optimization and the architecture is easily
scalable to support various network sizes. Fabricated in 65nm CMOS, the digital
base-band consumes 0.9uW (V_DD=0.37V) in sub-threshold operation at 250kbps,
with appropriate 97% wake-up beacon detection and 0.04% false alarm
probabilities. The circuit is fully functional at a minimum V_DD of 0.23V at
f_max=5kHz and 0.018uW power consumption. Based on these results we show that
our digital base-band can be used as a companion to compensate for front-end
implementation losses resulting from the limited wake-up receiver power budget
at a negligible cost. This implies an improvement of the practical sensitivity
of the wake-up receiver, compared to what is traditionally reported.Comment: Submitted to IEEE Sensors Journa
- âŠ