Selective Filters and Tunable Sinusoid Oscillator Using a CDBA

Rabindranath Nandi, Palaniandavar Venkateswaran, Sagarika Das

B. P. Poddar Institute of Management & Technology, Kolkata, India.
Department of Electronics & Telecommunication Engineering, Jadavpur University, Kolkata, India.

DOI: 10.4236/cs.2013.42030                

Abstract

The realization of some new selective filters using single current differencing buffered amplifier (CDBA) and few RC components is presented. The same topology provides lowpass (LP), bandpass (BP) and highpass (HP) characteristics with appropriate choice and location of the RC components in the circuit. Incorporation of a suitable feedback loop through a voltage buffer unity-gain cell yields a tunable sinusoid oscillator. Effects of the device port mismatch errors (ε) and parasitic z-node capacitance (C_z) of the CDBA element are shown to be insignificant and corresponding sensitivities are extremely low. Satisfactory experimental verifications of the filter quality (Q) and oscillator tuning range (500 KHz ≤ f_o ≤ 5 MHz) are carried out.

Keywords

Current Differencing Buffered Amplifier; Selective Filter; Sinewave Generator; Tunable Oscillator

Conflicts of Interest

The authors declare no conflicts of interest.

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