Research On Single-pole And Multi-throw Switches In 40-nm CMOS

In recent decades,wireless communication system has experienced explosive growth,and radio frequency(RF)transceiver module is an indispensable part of wireless communication system.Transceiver needs a single-pole double-throw(SPDT)T/R switch to provide isolation between transmitter and receiver.The insertion loss and bandwidth extention of SPDT switch is crucial for the further development of ultra-wideband and multi-mode wireless communication systems.The basic operation principle,typical circuit topology and port matching network of single-pole multi-throw(SPMT)switches are studied in this paper,The SPDT switch used in the RF transceiver module and the SPMT switch applied in the switching beam array are firstly investigated.The circuit structure and corresponding advantages and disadvantages of the SPMT(SPDT,SP4T,SP6T,SP8T)switches which work in the ragnge from DC to 50GHz are theoretically studied and analyzed.The research of this paper focuses on single-pole double-throw(SPDT)switches with transistors in series,series-shunt,and differential structures,and the effects of different port impedance matching networks(T-type,?-type,L-type)on SPMT switches are analyzed,At the same time,the technologies such as the Deep n-well technology and the substrate floating technology to improve the insertion loss(IL)and isolation(ISO)of SPMT is studied.The final analysis and comparison show that the series-shunt structure of transistors is suitable for SPDT,SP4T and SP6T switches,while the series structure of transistors is suitable for SP8T switch.Meanwhile,the ?-type input port impedance matching network enables the SPMT switch to have the best resonance.After the above research and analysis,in this paper,the circuit structure and matching network of SPDT,SP4T,SP6T and SP8T switches are analyzed and designed respectively based on 40nm low leakage CMOS process.In this paper,the design and simulation of SPMT(SPDT,SP4T,SP6T,SP8T)switches that the bandwidth greater than 20GHz,return loss below-18dB,insertion loss less than-3dB,isolation larger than 32dB were complted.Finally,the layout of the SPMT switch circuit is designed.The chip area of the SPDT switch is 561*571um2.The simulation results show that the post-simulation results show an increase in the insertion loss and return loss of the SPMT switches compared with the previous simulation results.The SPMT switches designed in this paper can meet the performance requirements of switches in multi-band,multi-mode and other wireless communication systems.