微波注入反相器基本电路的非线性效应

Nonlinear disturbance on three-inverter circuit under microwave injection

采用理论分析和微波注入实验相结合的方法,分别研究了以74HC04和74LVCU04A两种芯片为核心的反相器基本缓冲及数模转换电路的微波效应问题,通过反相器闩锁过程对非线性扰乱进行了机理分析,并利用微波注入实验详细分析了非线性扰乱效应的微波有效功率阈值及其随频率、脉冲宽度的变化。实验结果表明:在固定环境温度条件下,有效注入功率大于33dBm,频率在3GHz以下的微波均可使74HC04效应电路的非线性扰乱强度达到10%以上;有效注入功率大于30dBm,频率在3GHz以下的微波均可使74LVCU04A效应电路的非线性扰乱强度达到10%以上。相同非线性扰乱强度的注入有效功率阈值近似随频率的提高而增大。非线性扰乱阈值随注入微波信号脉宽变化明显,拐点为40～70ns不等,与反相器中的互补型金属氧化物半导体器件寄生三级管的导通电流积累有关。

With the analog-to-digital converter of three inverters,theoretical analysis and injection experiment of microwave effects are carried out on circuit unit level.The core chip of the circuit is 74HC04 or 74LVCU04A inverter.The latch process of the inverter is used to explain the nonlinear disturbance.The study is concentrated on the microwave effects on the circuit operating.Under the variation parameters of injected microwave pulse,such as amplitude,carrier frequency,and pulse width.At a fixed temperature,the threshold of effective injected microwave power for nonlinear disturbance of 10 % is 33 dBm for 74HC04 and 30 dBm for 74LVCU04A,when the carrier frequency of the injected microwave is below 3 GHz.The threshold increases with the increase of the carrier frequency.Additionally,it has a strong relation to the pulse width of the injected microwave,and the inflection point of the relation curves is about 40 to 70 ns,which is related to the turn-on current of the CMOS parasitic three triode in the inverter circuit.