Abstract

Wideband analog signal processing systems are useful in many applications, such as telecommunication, multimedia and consumer electronics. An analog filter is an important subsystem in such systems. Among the existing realization methods of continuous-time domain integrated analog filter, OTA-C topology is the most useful one, and it offers good performances with lower power consumption and high frequency operation. In this work, several existing OTA cells selected from literature are studied. Based on the comparison of g m value, bandwidth, output resistance, and dynamic range in terms of DC power dissipation and substrate area requirement, an optimum OTA cell is selected for the implementation of wideband OTA-C filter. Using selected OTA cell as the basic building block, a fully differential highly linear, very wideband sixth-order filter is designed using 0.18 om CMOS technological process. Three identical biquads are connected using PRB (Primary Resonator Block) technique to realized a sixth order bandpass filter that has a passband from 2 MHz to 400 MHz. Simulation results show that the filter consumes 80.70 mW of power with supply voltages of ±1.5 V. The dynamic range for % THD with 0.42 V (peak-to-peak) at 100 MHz is close to 40 dB and the third order intermodulation intercept (IIP 3 ) is -27.29 dBW (i.e. 2.71 dBm)