The switch LSI described here takes advantage of the special characteristics of fully-depleted CMOS/SIMOX devicesthat is, source/drain capacitances and threshold voltages that are lower than those of conventional bulk CMOS devicesto boost the I/O bit rate. The double-edge triggered MUX/DEMUX which uses a frame synchronization logic, and the active-pull-up I/O provide a 144-pin, 2. 5-Gbps/pin interface on the chip. The 220-kgate rerouting banyan switching network with 110-kbit RAM operates at an internal clock frequency of 312 MHz. The CMOS/SIMOX LSI consumes 8. 4 W when operating with a 2-V power supply, and has four times the throughput of conventional one-chip ATM switch LSIs.

This paper describes the design and evaluation of a high-performance multicast ATM switch and its feasibility study, including its 40 Gbit/s LSI packaging. The multicast switch is constructed using a serial combination of rerouting networks and employs an adapted Boolean interval-splitting scheme for a generalized self-routing algorithm. Analysis and computer simulation results show that the cell loss probability is easily controlled by increasing the number of switching stages. It is shown that the switch configuration can be transformed into other patterns to be built from banyan-based subnetworks of arbitrary size for LSI packaging. It is also shown that an LSI chip integrating an 88 banyan-based subnetwork using 0. 25-µm CMOS/SIMOX technology can attain a 40-Gbit/s switching capability.

We have developed a design technique for static logic circuits. Using this technique, we designed 1/2 divider-type 1:4 demultiplexer (DEMUX) and 2:1 selector-type 4:1 multiplexer (MUX) circuits, each of which is a key component in high-speed data multiplexing and demultiplexing. These circuits consist of double rail flip-flops (DR F/F). These flip-flops have a smaller mean internal capacitance than single rail flip-flops, making them suitable for high-speed operation. The DR F/F has a symmetric structure, so the double rail toggle flip-flop can put out an exactly balanced CK/CKN signal, which boosts the speed of the data flip-flops. The double rail structure enables 30% faster operation but consumes only 17% more power (per GHz) than a single rail circuit. In addition, our 0.25-µm process technology provides a 70% higher frequency operation than 0.5-µm process technology. At the supply voltage of 2.2 V, the DEMUX circuit and the MUX circuit operate at 4.55 GHz and 2.98 GHz, respectively. In addition, the 0.25-µm DEMUX circuit and the MUX circuit respectively consume 6.0 mW/GHz and 13.7 mW/GHz (＠1.3 V), which are only 12% of the power consumed by 3.3-V 0.5-µm circuits. Because of its high-speed and low-power characteristics, our design technique will greatly contribute to the progress of large-scale high-speed telecommunication systems.