Switched Capacitor Biquad Filter Using CDTA


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.

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Dehran, M. , Singh, I. , Singh, K. and Singh, R. (2013) Switched Capacitor Biquad Filter Using CDTA. Circuits and Systems, 4, 438-442. doi: 10.4236/cs.2013.46057.

Conflicts of Interest

The authors declare no conflicts of interest.


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