A state of art design technique of broadband Active/Passive SPST switch using 130nm SiGe BiCMOS technology

Abstract

This paper presents the state of the art for new ultra-wideband active/passive RF SPST switches that can not only reduce insertion loss or potentially generate gain, but also significantly increase isolation. The proposed active/passive ultra-wideband RF SPST switch design using 130 nm SiGebased BiCMOS technology. This switch operates from 5 GHz to 45 GHz with high isolation and low gain/loss Two identical SPST switches and a broadband active balun make up the proposed RF switch. The RF leakage current cancellation technique improved the isolation of the switch. By connecting two identical off switches with an active balun, the stray RF signal has been considerably diminished or eliminated. The active balun contributes to the switch's isolation when it is off and offers potential gain when it is operating in the on-state. The active balun operates over an extremely wide bandwidth while consuming little DC power. The performance of the designed active/passive RF switch is exceptional from 5 GHz to 45 GHz. This switch offers a gain of +1.928 dB to+310.083 mdB from 5 GHz to 10 GHz and a very good insertion loss <-0.28 dB from 10 GHz to 45 GHz in schematic simulation. This switch provides better isolation than <-49.94 dB from 5 GHz to 45 GHz in schematic simulation. The input return loss of the switch varies from -2.6205 dB to -10.0289 dB from 5 GHz to 15.0725 GHz and -10.0725 dB from 15 GHz to 45 GHz in schematic simulation. The switch output return loss is better than -4.5 dB from5 GHz to 45 GHz in the schematic simulation. This switch act as active as well as passive, therefore stability is one of important parameter from design point of view. Therefore, switch stability factor checked in "on “condition and "off" condition. The stability factor(k) of switch is greater than 2.88 in "on" condition and stability factore (k) of switch is greater than 45 in "off" condition in schematic simulation