一种抗辐照加固高压DAC的设计  

Design of a radiation hardened high voltage DAC

作　　者：苏晨[1] 雷郎成[1] 高炜祺[1] SU Chen;LEI Langcheng;GAO Weiqi(Sichuan Institute of Solid-State Circuits,China Electronics Technology Group Corp,Chongqing 400060,China)

机构地区：[1]中国电子科技集团公司第二十四研究所,重庆400060

出　　处：《空间电子技术》2021年第3期49-52,共4页Space Electronic Technology

摘　　要：高压DAC由于采用了大量厚栅氧MOS管,在总剂量辐照环境下会引起器件参数漂移、漏电流增加等。通常的解决方法是衬底隔离寄生MOS管、NMOS管环栅设计、栅氧工艺优化等方法,而很少分析辐照条件下,电压和电路结构对MOS管阈值和漏电的影响。文章对总剂量辐照条件下,不同电压对MOS器件阈值和漏电的作用进行综合分析;重点研究了MOS器件的不同阈值变化对DAC影响的机理。并提出一种低电源电压的设计思路,有效提高了高压DAC的抗辐照能力。最后,利用内置LDO和输出运放钳位降压的设计,将高压DAC的抗辐照能力提高至50k rad(Si)。For existing thick gate-oxide MOS transistor,total dose radiation result to parameter drift and leakage current increase of high voltage DAC.The usual solution is isolation parasitism MOS transistor by P injection,design of ring-gate NMOS transistor,optimization of gate-oxide process,etc.While the study about influence to threshold volt and leakage current of MOS transistor by circuit voltage and structure is rarely reported.Because of different supply voltage,the effect to threshold volt and leakage current of MOS transistor by total dose radiation were analyzed.The influence mechanism to DAC by different threshold volt changing were emphatically studied.A design ideas of lower supply voltage to raising radiation hardened level is presented.Finally,using the clamp design of built-in LDO and Output Op Amp,the radiation hardened ability of the high voltage DAC is improved to 50k rad(Si).

关 键 词：高压DAC MOS管阈值 NMOS管环栅 总剂量辐照 

分 类 号：V443.4[航空宇航科学与技术—飞行器设计]