Operational Transconductance Amplifiers (OTAs) with high linearity and wide input range characteristics have become a focus of interest for analog continuous-time circuits. In this research, we intend to develop a low distortion, wide swing CMOS OTA. The supply voltage is 5V. Simulation results show that the OTA is linear, tunable and wide swing. The transconductance can be tuned from 23£gA/V to 37£gA/V. When a 3VPP input signal with 1MHz is applied, THD of the OTA is 51dB. The OTA is used to realize a 1-MHz 7th-order Butterworth lowpass filter. When a 1VPP input signal with 100KHz is applied, THD of the lowpass filter is 50dB. All the circuits are designed based on the UMC 0.5£gm 2p2m CMOS process technology.

We developed low voltage wide swing second generation current conveyors(CCII) with the application to a insensitive Butterworth second-order low-pass filter. All circuits are designed using the parameters of TSMC 1P4M 0.35um process. The minimum supply voltage of CCII(1) circuit is |Vtp|+3Vod. The supply voltage of CCII(2) circuit is |Vtp|+2Vod. The voltage swing of the CCIIs are almost rail to rail.