A power efficient 2Gb/s transceiver in 90nm CMOS for 10mm On-Chip interconnect

Global on-chip data communication is becoming a concern as the gap between transistor speed and interconnect bandwidth increases with CMOS process scaling. In this paper a low-swing transceiver for 10mm long 0.54μm wide on-chip interconnect is presented, which achieves a similar data rate as previous designs (a few Gb/s), but at much lower power than recently published work. Both low static power and low dynamic power (low energy per bit) is aimed for. A capacitive pre-emphasis transmitter lowers the voltage swing and increases the bandwidth using a simple inverter based transceiver and capacitive coupling to the interconnect. The receiver uses Decision Feedback Equalization with a power-efficient continuous-time feedback filter. A low power latch-type voltage sense amplifier is used. The transceiver, fabricated in a 1.2V 90nm CMOS process, achieves 2Gb/s. It consumes only 0.28pJ/b, which is 7 times lower than earlier work

CMOS transceiver with baud rate clock recovery for optical interconnects

An efficient baud rate clock and data recovery architecture is applied to a double sampling/integrating front-end receiver for optical interconnects. Receiver performance is analyzed and projected for future technologies. This front-end allows use of a 1:5 demux architecture to achieve 5Gb/s in a 0.25 μm CMOS process. A 5:1 multiplexing transmitter is used to drive VCSELs for optical transmission. The transceiver chip consumes 145mW per link at 5Gb/s with a 2.5V supply

40.4fJ/bit/mm Low-Swing On-Chip Signaling with Self-Resetting Logic Repeaters Embedded within a Mesh NoC in 45nm SOI CMOS

Mesh NoCs are the most widely-used fabric in high-performance many-core chips today. They are, however, becoming increasingly power-constrained with the higher on-chip bandwidth requirements of high-performance SoCs. In particular, the physical datapath of a mesh NoC consumes significant energy. Low-swing signaling circuit techniques can substantially reduce the NoC datapath energy, but existing low-swing circuits involve huge area footprints, unreliable signaling or considerable system overheads such as an additional supply voltage, so embedding them into a mesh datapath is not attractive. In this paper, we propose a novel low-swing signaling circuit, a self-resetting logic repeater, to meet these design challenges. The SRLR enables single-ended low-swing pulses to be asynchronously repeated, and hence, consumes less energy than differential, clocked low-swing signaling. To mitigate global process variations while delivering high energy efficiency, three circuit techniques are incorporated. Fabricated in 45nm SOI CMOS, our 10mm SRLR-based low-swing datapath achieves 6.83Gb/s/µm bandwidth density with 40.4fJ/bit/mm energy at 4.1Gb/s data rate at 0.8V.United States. Defense Advanced Research Projects Agency. The Ubiquitous High-Performance Computing Progra

Low-swing signaling for energy efficient on-chip networks

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 65-69).On-chip networks have emerged as a scalable and high-bandwidth communication fabric in many-core processor chips. However, the energy consumption of these networks is becoming comparable to that of computation cores, making further scaling of core counts difficult. This thesis makes several contributions to low-swing signaling circuit design for the energy efficient on-chip networks in two separate projects: on-chip networks optimized for one-to-many multicasts and broadcasts, and link designs that allow on-chip networks to approach an ideal interconnection fabric. A low-swing crossbar switch, which is based on tri-state Reduced-Swing Drivers (RSDs), is presented for the first project. Measurement results of its test chip fabricated in 45nm SOI CMOS show that the tri-state RSD-based crossbar enables 55% power savings as compared to an equivalent full-swing crossbar and link. Also, the measurement results show that the proposed crossbar allows the broadcast-optimized on-chip networks using a single pipeline stage for physical data transmission to operate at 21% higher data rate, when compared with the full-swing networks. For the second project, two clockless low-swing repeaters, a Self-Resetting Logic Repeater (SRLR) and a Voltage-Locked Repeater (VLR), have been proposed and analyzed in simulation only. They both require no reference clock, differential signaling, and bias current. Such digital-intensive properties enable them to approach energy and delay performance of a point-to-point interconnect of variable lengths. Simulated in 45nm SOI CMOS, the 10mm SRLR featured with high energy efficiency consumes 338fJ/b at 5.4Gb/s/ch while the 10mm VLR raises its data rate up to 16.OGb/s/ch with 427fJ/b.by Sunghyun Park.S.M

A Survey Addressing on High Performance On-Chip VLSI Interconnect

With the rapid increase in transmission speeds of communication systems, the demand for very high-speed lowpower VLSI circuits is on the rise. Although the performance of CMOS technologies improves notably with scaling, conventional CMOS circuits cannot simultaneously satisfy the speed and power requirements of these applications. In this paper we survey the state of the art of on-chip interconnect techniques for improving performance, power and delay optimization and also comparative analysis of various techniques for high speed design have been discussed

Analog/RF Circuit Design Techniques for Nanometerscale IC Technologies

CMOS evolution introduces several problems in analog design. Gate-leakage mismatch exceeds conventional matching tolerances requiring active cancellation techniques or alternative architectures. One strategy to deal with the use of lower supply voltages is to operate critical parts at higher supply voltages, by exploiting combinations of thin- and thick-oxide transistors. Alternatively, low voltage circuit techniques are successfully developed. In order to benefit from nanometer scale CMOS technology, more functionality is shifted to the digital domain, including parts of the RF circuits. At the same time, analog control for digital and digital control for analog emerges to deal with current and upcoming imperfections

A 90 nm CMOS 16 Gb/s Transceiver for Optical Interconnects

Interconnect architectures which leverage high-bandwidth optical channels offer a promising solution to address the increasing chip-to-chip I/O bandwidth demands. This paper describes a dense, high-speed, and low-power CMOS optical interconnect transceiver architecture. Vertical-cavity surface-emitting laser (VCSEL) data rate is extended for a given average current and corresponding reliability level with a four-tap current summing FIR transmitter. A low-voltage integrating and double-sampling optical receiver front-end provides adequate sensitivity in a power efficient manner by avoiding linear high-gain elements common in conventional transimpedance-amplifier (TIA) receivers. Clock recovery is performed with a dual-loop architecture which employs baud-rate phase detection and feedback interpolation to achieve reduced power consumption, while high-precision phase spacing is ensured at both the transmitter and receiver through adjustable delay clock buffers. A prototype chip fabricated in 1 V 90 nm CMOS achieves 16 Gb/s operation while consuming 129 mW and occupying 0.105 mm^2