磁共振快速T/R开关驱动器研制  

A High-Speed Driver for NMR T/R Switch

作　　者：刁玉剑 谢君尧 徐俊成[1] 蒋瑜[1] 

机构地区：[1]上海市磁共振重点实验室,华东师范大学物理系,上海200062

出　　处：《波谱学杂志》2016年第1期37-43,共7页Chinese Journal of Magnetic Resonance

基　　金：国家高技术研究发展计划“863计划”资助项目(2014AA123401)

摘　　要：在磁共振T/R开关和主动失谐线圈中广泛使用PIN管,由外部驱动器向PIN管提供驱动电源,控制其导通或截止,从而达到开关切换和线圈失谐的目的.因此,驱动器的性能直接影响T/R开关和线圈的性能.该工作提出了一种新的T/R开关驱动器设计方案.电路中门控信号与驱动电源互相隔离,同时包含了场效应管死区调整电路,提高了电路稳定性和灵活性.该电路开关切换时间可达500 ns,驱动电压和电流理论上分别可达400 V和10 A以上,具有快速、驱动能力强等特点.可用于快速T/R开关和主动失谐线圈的驱动、缩短死时间、减小发射线圈和接收线圈间的耦合.T/R switch is a device that switches between the radio frequency （RF） transmission path and the signal reception path, and enables rapid tuning and detuning of RF coils. PIN diodes are widely utilized in modem T/R switch and tunable coil configurations, given that they operate as variable resistors controlled by DC current at RF frequencies. Since the PIN diode can only work with a driver providing the forward or reverse bias supply, its performance is significantly influenced by the capability of the driver. This paper presents a driver design with high driving speed, and high voltage and current driving capabilities. In this design, the control signal was separated from the high power driving supplies. The driver had a switching time within 500 ns with an output voltage over 400 V and an output current over 10 A. It can be applied to drive fast and high-power T/R switches.

关 键 词：核磁共振仪器 T/R开关驱动器 光电隔离 PIN管 大功率 MOSFET管 

分 类 号：O482.53[理学—固体物理]