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The article features Tadahiro Kuroda and Stephen V. Kosonocky and the selection of the best papers from the 2005 Symposium on VLSI Circuits, which was held at the Rihga Royal Hotel, Kyoto, Japan on June 16-18, 2005. The Symposium marked its 19th annual meeting, establishing itself as a major international forum presenting developments in VLSI circuit design. Tadahiro Kuroda received the Ph.D. degree in electrical engineering from the University of Tokyo and worked for Toshiba Corporation while Stephen V. Kosonocky received the Ph.D. degree from Rutgers University in New Jersey and worked for Siemens, Samsung and IBM.

Introduces the articles in the April 2005 issue of the periodical "IEEE Journal of Solid-State Circuits". Papers from the 2004 Symposium on VLSI Circuits; Number of submissions accepted by the Symposium.

A new ultralow voltage 2.4 GHz voltage-controlled oscillator (VCO) and a divide-by-2 frequency divider circuits operating in a CMOS sub-threshold region using a transformer technique have been developed. In the sub-threshold region, the CMOS transistor high frequency performances are decreased to the point where oscillation and frequency division are challenging to achieve. The new proposed VCO uses the transformer feedback complementary VCO technique to improves VCO negative feedback gain. The circuits have been fabricated in a 65 nm standard CMOS process. The oscillation frequency is designed at 2.4 GHz under a 300 mV supply voltage. The total power consumption is 202 µW with noise performance of −96 dBc/Hz at 1 MHz offset. The new proposed frequency divider circuit consists of two stages master-slave D-type flip-flop (DFF). The DFF differential input is coupled to a transformer circuit instead of transistors to reduce the number of stacks. The minimum operating supply voltage is 300 mV with power consumption of 34 µW with a free-run frequency of 1.085 GHz. [ABSTRACT FROM AUTHOR]

An asynchronous pulse transmitter is proposed to achieve low power in inductive-coupling link. The conventional asynchronous transmitter, H-bridge inductive-coupling transmitter, consumes large static (DC) current consumption. Therefore the transmit power dissipation is dominant in the total inductive-coupling power dissipation. The proposed pulse inductive-coupling transmitter eliminates the static (DC) current consumption. It provides linear power scalability which significantly reduces the power consumption especially at low data rate operation for low-power mobile applications. To verify the proposed technique, we designed and fabricated test chips in TSMC 0.18 µm complementary metal oxide semiconductor (CMOS) technology. Both proposed pulsed transmitter and conventional H-bridge transmitter is implemented in the test chip for comparison. Power reduction to 1/4 at 1.5 Gbps and 1/60 at 100 Mbps is achieved compared to the conventional transmitter. Also a crosstalk immune inductive-coupling receiver is presented for low-power relayed transmission using the proposed pulse transmitter. Crosstalk guard circuit is implemented in the receiver to ignore crosstalk. Data is successfully transferred using relayed transmission with proposed transceiver at up to 400 Mbps. [ABSTRACT FROM AUTHOR]

The rapid performance progress in processors and memory cores by technology scaling requires further improvement in interface bandwidth. However, interface bandwidth is not keeping up with the processing speed of the core and is becoming a bottleneck in system performance. To fill the performance gap, wideband lowpower low-cost interfaces are strongly demanded. A wireless proximity interface that uses inductive coupling is one such interface expected to be used for interchip links in high-performance 3D system integration. Inductive coupling interfaces use the magnetic near-field induced by micro-coils. The coils (channels) can be arranged in a dense array because magnetic near-field localizes in the proximity of each coil, and crosstalk between the channels is small. Therefore, inductive coupling interfaces are suitable for wideband low-cost proximity communication. An inductive coupling interface can also realize highly reliable communication with low power consumption. Evaluation systems developed to study the performance of inductive coupling interfaces have demonstrated the feasibility of the interfaces in a wide range of applications. [ABSTRACT FROM PUBLISHER]

H2 and NH3 detection with low power consumption was demonstrated by integrated chemiresistive Pt and PtRh nanosheet sensors on glass substrates. The self-heating effects realized low power and local heating of metal nanosheet sensors, enabling the integration of sensors with different operating temperatures. Based on different resistance changes in Pt and PtRh nanosheets toward H2 and NH3, the concentration of each gas was detected from a gas mixture by consuming around 1-mW power. For decreasing the power consumption and further integration of sensors, sensor scaling and pulsed operations were numerically and experimentally studied. In addition to good connectivity of metal nanosheet sensors to large-scale integration (LSI) circuits, improvements of the power consumption by sensor scaling were proven. The pulsed operations required for integrated sensor arrays maintained a sensor response, or a resistance change, of approximately 60%, even when the power consumption was reduced by 20%. [ABSTRACT FROM AUTHOR]