Novel Design Solution of Reconnection-less Electronically Reconfigurable Filter

L. Langhammer, R. Sotner, J. Dvorak (Brno Univ. of Techn., Czech Republic), T. Dostal (College of Polytechnics Jihlava, Czech Republic)

The paper presents a new design solution of a reconnection-less electronically reconfigurable filter (no manual reconnection or topology change is necessary) offering all standard 2nd-order transfer functions (low pass, band pass, high pass, band stop and all pass). The filter can also provide high-pass and low-pass function with transfer zero (HPZ, LPZ), direct transfer and high-pass function of the 1st-order. The design is based on well-known operational transconductance amplifiers (OTAs) and adjustable current amplifiers (ACAs). Moreover, the electronic control of the pole frequency and quality factor of the filter are available. The proposal is verified by PSpice simulations using commercially available devices.