Single input multiple output universal biquad using current mirrors

Abstract

A novel single-input second-order multifunction filter realized by employing current mirrors is introduced in this manuscript. The proposed topology offers simultaneously the lowpass, highpass, bandpass, and bandstop frequency responses. Other attractive characteristics are its potential for low-voltage operation and the electronic tuning. In addition, the only passive elements used for realizing the multifunction filters are grounded capacitors. The filter topology could become universal by employing additional circuitry. Simulation results confirm the correct operation of the proposed structure.

Universal biquad filters using low-voltage current mirrors

“…3 has better performance in terms of power dissipation, noise, dynamic range, and sensitivity of center frequency compared with that achieved by the topologies in [10,11]. The only drawback is that the orthogonal adjustment of x o and Q is achieved under the condition of equal transconductance parameters g m1 and g m2 , as in [10].…”

“…The proposed MISO universal biquad does not suffer from the requirement of manipulating its core structure as in [9] and, offers an almost 50% reduction of the required dc power dissipation compared with that required in the topology in [2]. The proposed SIMO universal biquad offers reduced power dissipation compared with that required in [10,11] and, simultaneously, it is improved in several performance factors. Due to the employment of current mirrors, the only required passive elements are grounded capacitors.…”

“…The main drawback of the topology in [9] is that manipulations of the core structure must be performed in order to become an actual universal biquad. SIMO universal biquad topologies have been introduced by authors in [10,11].…”