Characterization and Simulation of Second Generation Current Conveyors

Abstract

In last few decades, the demand of portable devices such as laptop, palmtop andcell phones is increased drastically. These devices use low supply voltages usingsingle cell battery. Research in analog integrated circuits has recently gone in thedirection of low voltage (LV) low-power (LP) design especially in the environment ofportable systems. These LV circuits have to show also a reduced power consumptionto maintain a longer battery lifetime. In this area traditional voltage-mode techniquesare going to be substituted by the current-mode approach which has the advantageto overcome the gain-bandwidth product limitation typical of operational ampliers.Then they do not require high voltage gains and have good performance in terms ofspeed bandwidth and accuracy. Inside the current-mode architectures the current-conveyor (CCII) can be considered the basic circuit block because all the active devicescan be made of a suitable connection of one or two CCIIs. CCII is particularlyattractive in portable systems where LV LP constraints have to be taken into account.In fact it suers less from the limitation of low current utilization while showing fulldynamic characteristics at reduced supplies (especially CMOS version) and good highfrequency performance. Recent advances in integrated circuit technology have alsohighlighted the usefulness of CCII solutions in a large number of signal processingapplications.This project describes dierent topologies of CCIIs. All topologies have beensimulated in dierent CMOS process technologies using Eldo Spice tool and layoutis made using Mentor Graphics Back End tools like IC Station and DA-IC. Dierentcharacteristics such as gain, bandwidth, terminal impedances, slew rate, dynamicrange, input-output current characteristic and oset are measured and tabulated forall the CCII topologies.