Hindawi Publishing Corporation Journal of Electrical and Computer Engineering Volume 2011, Article ID 175130, 6 pages doi:10.1155/2011/175130 Research Article New Topologies of Lossless Grounded Inductor Using OTRA Rajeshwari Pandey, 1 Neeta Pandey, 1 Sajal K. Paul, 2 A. Singh, 1 B. Sriram, 1 and K. Trivedi 1 1 Department of Electronics and Communication, Delhi Technological University, Bawana Road, Delhi 110042, India 2 Department of Electronics Engineering, Indian School of Mines, Dhanbad 826004, India Correspondence should be addressed to Sajal K. Paul, sajalkpaul@rediffmail.com Received 28 March 2011; Revised 14 June 2011; Accepted 14 June 2011 Academic Editor: Raj Senani Copyright © 2011 Rajeshwari Pandey et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Two alternate topologies of lossless grounded inductor have been proposed using operational transresistance amplifier (OTRA). Three applications using the proposed inductors are also included. PSPice simulation and experimental results have been included to demonstrate the performance and verify the theoretical analysis. 1. Introduction Recently the operational transresistance amplifier (OTRA) has emerged as alternate important analog building block as it inherits all the advantages offered by current mode techniques. The OTRA is a high-gain current input voltage output device. The input terminals of OTRA are internally grounded, thereby eliminating response limitations due to parasitic capacitances and resistances at the input. Although the OTRA is commercially available from several sources under the name of current differencing amplifier or Norton amplifier, it has not gained attention until recently. These commercial realizations do not provide internal ground at the input port and allow the input current to flow in one direction only. The former disadvantage limits the functionality of the OTRA where as the later forces to use external DC bias current leading to complex and unattrac- tive designs [1]. Several high-performance CMOS OTRA topologies have been proposed in literature [1–4] leading to growing interest in OTRA-based analog signal processing circuits. In the recent past OTRA has been extensively used as an analog building block for realizing a number of signal processing circuits such as filters [5–8], oscillators [9, 10], multivibrators [11, 12], and immittance simulation circuits [9, 13–15], an application which has been dealt with in this paper. A number of grounded parallel immittance topologies using single OTRA are proposed in [13]. However none of these configurations can realize a lossless grounded inductor. The structure in [14] presents simulation of lossless negative grounded inductance. Lossless grounded inductor simulators using two OTRAs, five resistors, and one capacitor are presented in [9, 15]. In this paper two additional topologies of lossless grounded inductor using two OTRAs, five resistors, and one capacitor are reported. In these topologies five passive elements out of six are grounded as compared to four grounded elements in [9, 15]. Some applications of the proposed topologies are also presented. 2. Circuit Description OTRA is a three-terminal device, shown symbolically in Figure 1 and its port relations can be characterized by the following matrix: ⎡ ⎢ ⎢ ⎢ ⎣ V p V n V O ⎤ ⎥ ⎥ ⎥ ⎦ = ⎡ ⎢ ⎣ 0 0 0 0 0 0 R m -R m 0 ⎤ ⎥ ⎦ ⎡ ⎢ ⎢ ⎢ ⎣ I p I n I O ⎤ ⎥ ⎥ ⎥ ⎦ . (1) For ideal operations the transresistance gain R m approaches infinity and forces the input currents to be equal. Thus OTRA must be used in a negative feedback configuration. The proposed lossless grounded inductor topologies are shown in Figure 2. Routine analysis of the circuit of