Switched Capacitor Biquad Filter Using CDTA

Meeti Dehran, Indu Prabha Singh, Kalyan Singh, Rabindra Kumar Singh

Department of Electrical and Electronic Engineering, Kamla Nehru Institute of Technology (KNIT), Sultanpur, India.
Department of Physics and Electronics, R.M.L. University, Faizabad, India.
epartment of Electronics and Communications Engineering, Shri Ramswaroop Memorial Group of Professional Colleges (SRMGPC), Lucknow, India.

DOI: 10.4236/cs.2013.46057                

Abstract

A switched capacitor biquad filter using current differencing transconductance amplifier (CDTA) is presented in this paper. The proposed circuit employs only one CDTA, two virtually grounded capacitors and one switched capacitor. It is a resistorless circuit, so it is beneficial to IC implementation in terms of space consideration. The proposed circuit is a second order single input multiple output (SIMO) current-mode filter. This filter can simultaneously realize all basic filter functions high pass, low pass and band pass responses without any component-matching conditions. All the active and passive sensitivities are low. The natural angular frequency (ω₀) and quality factor (Q) of proposed filter can be electronically controlled. Owing to current mode operation it consumes less power. PSPICE simulation results are used to verify the theoretical analysis.

Keywords

Current Differencing Transconductance Amplifier (CDTA); Biquad Filter; Current-Mode Circuit

Conflicts of Interest

The authors declare no conflicts of interest.

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