Universal Current-Mode Biquad Filter Using a VDTA

Abstract

This paper presents a new current-mode single input multi output (SIMO) type biquad employing one voltage differencing transconductance amplifier (VDTA), two grounded capacitors and a single grounded resistor. The configuration realizes all basic filter functions (i.e. Low Pass (LP), High Pass (HP), Band Pass (BP), Notch (BR) and All Pass (AP)). The natural frequency (ω 0 ) and bandwidth (BW) are independently tunable. The workability of proposed configuration has been verified using SPICE simulation with TSMC CMOS 0.18 μm process parameters.

Tunable oscillator derived from Colpitts structure with simply controllable condition of oscillation and synthetic inductor based on current amplifier and voltage differencing transconductance amplifier

“…Voltage differencing transconductance amplifier (VDTA) [1] is quite new active element and it is very useful for our intentions in synthetic inductance equivalent. This element received attention in some applications that were discussed in recent works (active filters [16][17][18], oscillators [19][20]). We can also use knowledge of application of VDTA as inductance simulator presented in [21].…”

Novel current mode electronically tunable lossless integrator employing VDTA

“…Therefore, the aim of this paper is to present a lossless CM integrator configuration with following positive features: The VDTA is a popular active building block proposed in [16] finds several applications in analog filter designing [17][18][19], oscillators [20][21][22] and inductor simulators [21]. A single VDTA based trans-admittance mode integrator has been proposed in [23] but there is no current-mode integrator employing VDTA is available in literature.…”

Current Mode Universal Filter Using Single Current Controlled Differential Difference Current Conveyor Transconductance Amplifier

“…The current mode active blocks may process signals in voltage as well as current mode. A number of current mode filters using various analog building blocks (ABB) are available in literature under the classification of multi-input multi-output (MIMO) [2]- [5], single-input multioutput (SIMO) [6]- [11] and multi-input single-output (MISO) [12]- [24]. In addition, a range of current conveyor blocks with inbuilt transconductance amplifier (TA) in monolithic chip, such as current conveyor transconductance amplifier (CCTA) [25], current difference transconductance amplifier (CDTA) [26], current controlled current conveyor transconductance amplifier (CCCCTA) [27], differential voltage current conveyor transconductance amplifier (DVCCTA) [19], differential difference current conveyor transconductance amplifier (DDCCTA) [4], differential voltage current controlled conveyor transconductance amplifier (DVCCCTA) [28] and current controlled differential difference current conveyor transconductance amplifier (CCDDCCTA) [29], have emerged in last few years.…”