International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 06 Issue: 10 | Oct 2019 www.irjet.net p-ISSN: 2395-0072 © 2019, IRJET | Impact Factor value: 7.34 | ISO 9001:2008 Certified Journal | Page 1239 Design and Analysis of Low Cost Line Impedance Stabilization Network for ISM Equipment P. Priyadharsini 1 , Dr. S. Lakshmi 2 1 PG Scholar, AppliedElectronics, RVSCE, Dindigul, India 2 Assistant Professor, Department of ECE, RVS CE, Dindigul, India -----------------------------------------------------------------------***------------------------------------------------------------------------ Abstract -EMI/EMC testing is done to calculate the ability of the device which meets out all the required characteristics needed by a product to enter into the market. It includes immunity testing and emission testing. Immunity testing shows how a device will react when it is exposed in an electromagnetic energy. Emission testing measures the amount of EMI generated by the device. The device which fails to meet the EMI/EMC test Standard will lead to a number of negative consequences. Inorder to carry out this emission testing a low cost Line Impedance Stabilization Network (LISN) is proposed. Typical LISN is nothing but a filter placed between the source and EUT to create known impedance. LISN is particularly used to remove the unwanted RF signals from the power source. In this project the LISN is designed by using ADS software. LISN is designed by combining a low pass filter and the band pass filter inorder to provide stable input impedance followed in the CISPR-11 standard. Spectrum analyzer is connected at the end of the LISN to analyze the test equipment results. This LISN device will provide good input impedance to the test equipment at lowcost. Key Words: immunity testing, emission testing, Line Impedance Stabilization Network (LISN), ADS, CISPR-11 I. INTRODUCTION Products that enters into the market has to undergo EMI/EMC standard test.And all the EMI/EMC standard measurement has to follow the CISPR standards. These standards was categorised by their equipment and product class, by so many CISPR standards are available. One among that is CISPR-11 standard which is a standard used for ISM (Industrial, Scientific, Medical) equipment. EMC test involves Emission testing and immunity testing. Immunity testing is done to check the immunity level of the product when its supposed to be exposed in unpleasant environmental condition. Emission test is to determine whether the emission of EM energy of particular product affect the other product or not. To carry out the emission test the DUT must be connected to the power supply. Inorder to avoid the noise entering through power supply we use LISN in between the supply and DUT. The existing LISN is so costly. So, a low cost Line Impedance Stabilization Network (LISN) is proposed. II. RELATED WORKS Kang-Rong Li, Kye-Yak See, Rathnayaka Mudiyanselage Sooriya Bandara [1]proposed a conducted emission test for switch mode power supply which is used as a DUT here.In that they undergo incircuit Common mode and differential mode impedance measurement without LISN and then compare the results with LISN to see the difference in the outcome. The difference in their behavior of the system with and without LISN can be noted by using the Known impedance. In without LISN attenuation is poor when compared to the Presence of LISN in EMI/EMC standard test. Francois Ziade,Miha Kokalj, Mohamed Ouameur, Borut Pinter, Denis Belieres, Andre Poletaeff, Djamel Allal [2] proposed a LISN which is improved in accuracy. In this they provide calculable adapters for their accuracy measurement. They provide two sets of adapters for removing the error on magnitude and phase of the input impedance. In this frequency variation is calculated by COMSOL software. Adapters improve the reliability and accuracy and at the same time it reduces errors in both industry and test laboratories. Grobler, MN Gitau [3] proposed a pre-compliance measurement setup to measure the conducted emission of the product/system without using spectrum analyzerup to 100 MHz frequency range. In that they use oscilloscope for their noise measurement. In addition to that they undergo common mode and differential mode impedance measurement. These method will save time and cost.