Comparative performance study of multiple-input bulk-driven and multiple-input bulk-driven quasi-floating-gate DDCCs

This brief presents a comparative performance study of two recently presented techniques, the multiple-input bulk-driven (MI-BD) and the multiple-input bulk-driven quasi-floating-gate (MI-BD-QFG) MOS transistors (MOST). These techniques offer simplified CMOS structures of specific active elements and ensure near rail-to-rail operation capability under extremely low-voltage supply and reduced power consumption. However, to clarify the pros and cons of each technique, two Differential Difference Current Conveyors (DDCC) using MI-BD and MI-BD-QFG are compared. For the purpose of comparison, theoretical analysis such as small-signal model, open-loop gain, terminal resistances, gain bandwidth product, input referred thermal noise and maximum input range of the DDCCs are included. Furthermore, in order to provide a fair performance comparison both of the DDCCs is supplied with 0.4 V and consume same power 140 nW. The DDCCs were fabricated in a standard n-well 0.18 µm CMOS process from TSMC and hence the results are confirmed theoretically and experimentally.