Dual-Mode Multifunctional Reconnection-Less Reconfigurable Filter

Abstract

A novel solution of a reconnection-less reconfigurable filter is being presented. The filter works in the current mode, voltage mode, and mixed mode (voltage tocurrent) offering sixteen transfer functions in total. The structure utilizes a voltage differencing transconductance amplifier, current follower and voltage, and current amplifiers. The designed structure offers the control of the pole frequency and quality factor and the adjustment of the band-stop/band-pass area of available functions. The proposed design is supported by the PSpice simulations using available simulation models.

Novel current feedback operational amplifier‐based configuration that realizes a single‐input multiple‐output‐type universal active filter and a single‐resistance‐controlled oscillator

“…The parameters of the proposed filters can also be made electronically tunable by replacing the resistor R 3 with floating voltage controlled resistor (VCR) realizable with a single CFOA and single MOSFET in accordance with the circuit proposed in Senani 33 . In this manner, the electronic control of the parameters of the filters would be possible similar to the other techniques reported in previous works 34–40 …”

“…33 In this manner, the electronic control of the parameters of the filters would be possible similar to the other techniques reported in previous works. [34][35][36][37][38][39][40]…”

Reconnection-Less Reconfigurable Filter Based on Method of Unknown Nodal Voltages Using 4×4 Matrix

“…The solution of the above-described problem is the utilization of so-called reconnection-less reconfigurable (switchless) filters [12], [13], [14], [15], [16], [17], [18], [19], [20], [21] where the change of the transfer functions does not require any switching or topological changes. The general concept comes from the frequency filters operating in the microwave systems [12], [13], [14], [15] where the reconfiguration of the transfer function has its origin in the electromagnetic coupling of elements.…”

“…The general concept comes from the frequency filters operating in the microwave systems [12], [13], [14], [15] where the reconfiguration of the transfer function has its origin in the electromagnetic coupling of elements. The low-frequency (up to hundreds of megahertz) filters [16], [17], [18], [19], [20], [21] implement the reconnection-less reconfiguration by the utilization of electronically controllable active elements (the transfer function is changed by the setting of electronically controllable parameters of active elements employed in given topology). The electromagnetic coupling would be difficult to implement at these frequencies.…”

“…The same approach has been used for the presented design. Other common approach for the design of reconnection-less reconfigurable filters, used for filters in [20] and [21], is done by Signal Flow Graphs (SFGs) [23] (combination of Mason graphs [24] and Coates graphs [25] is typically used). The design in [16] is based on four Operational Transconductance Amplifiers (OTAs) with one grounded and one floating capacitor.…”