抗辐射加固的Σ-Δ调制器设计  

Design of the Radiation-Harden Sigma-Delta Modulator

作　　者：杜斌[1] 王颖[1] 陈杰[2] 刘云涛[1] 

机构地区：[1]哈尔滨工程大学信息与通信工程学院,哈尔滨150001 [2]中国科学院微电子研究所,北京100029

出　　处：《半导体技术》2014年第5期335-340,346,共7页Semiconductor Technology

基　　金：教育部科学技术研究重大项目(313017);教育部博士点基金资助项目(20122304110016);中央高校基本科研业务费专项资金资助项目(HEUCF130818)

摘　　要：针对辐射环境下的传感器应用，设计了一种抗辐射加固的∑－△调制器。通过对调制器非理想特性的建模来确定电路的设计参数。通过调节放大器的偏置电路使其在总剂量（TID）辐射引起的阈值偏移下仍然工作在饱和区。该调制器用3阶MASH结构实现，为了获得更好的线性度，采用单位量化技术。在TSMC2P4M工艺下，信号带宽为22kHz，电源电压3．3V，采样时钟频率为11．264MHz。仿真结果表明，功耗为39mw，可达到17bit以上的有效转换位数。在温度-40～85℃及辐射剂量100Mrad以下范围内，该设计均保持17bit以上的有效转换位数，能够在极端环境下有效工作。A radiation-harden Sigma-Deha ADC was presented for the application of the sensor in radiation environment. The circuit design specifications were determined by modelling the non-ideal be- havior of the modulator. The operation point of the opamp was made in the saturation region by optimiza- tion of the bias circuit under the threshold voltage shift caused by TID. The modulator was realized in three-order MASH structure, and the single bit quantization was used to obtain a better linearity. In the TSMC 2P4M process, the design featured an audio bandwidth of 22 kHz, a power supply 3.3 V at a sample frequency of 11. 264 MHz. The simulation results show that at the power consumption of 39 mW, the circuit maintains its 17 bit resolution under a simulated radiation dose lower than 100 Mrad and a var- ying temperature of-40-85 ℃ which can exhibit proper function in extreme environment.

关 键 词：∑-△调制器 抗辐射加固 非理想特性建模 全差分运算放大器 MASH结构 

分 类 号：TN76[电子电信—电路与系统]