A 4:1 MUX circuit using 1/4 micron CMOS/SIMOX for high-speed and low-power applications

We designed a new 4:1 multiplexer (MUX) circuit and fabricated it by 0.25-µm CMOS device process technology using Separation by IMplanted OXygen (SIMOX) wafer. This MUX circuit has a small number of fan-outs so that the SIMOX device, with smaller junction capacitance than a BULK device, effectively contributes to high-speed and low-power operation. We confirmed that the fabricated SIMOX MUX can operate at 2.7 GHz (@V DD = 2.0 V), which is 25% faster than the BULK MUX, and the power consumption is 19% less at the same speed and V DD. In addition, we confirmed that these improvements are mainly due to the reduced junction capacitance of SIMOX devices by estimating the gate speed in the critical path and the load capacitance in the SIMOX MUX circuit.