Study Of High-power Microwave (hpm) Effects Of The Digital Circuit

The CMOS inverters are normally chosen in digital circuit devices and it is the foundation of CMOS digital circuit analysis and design. So, the study of microwave interference effects on CMOS digital circuit-level device are mostly concentrated in CMOS inverter. In order to have a better understanding of these digital circuits effects of the electromagnetic interference and its interference mechanism, it is necessary to study the interference effects of microwave on the basic unit in integrated circuits such as CMOS inverter. In this paper we carried out a focusing study to disrupt and flip effects of the SN74AHC04 cascade CMOS inverter by directly injection of microwave pulse on it. The simulation and experiment were carried out and the results were studied to get the principal laws.A circuit simulation method of microwave interference on CMOS inverter is adopted in this paper. The central work of the simulation are on the responses of the inverter to the injected microwave pulse power, frequency, pulse width, pulse front edge, pulse back edge, and the operating voltage. A large number of experiments were still carried out to study the interference effects when cascaded CMOS inverters worked in high or low input voltage, rising edge or falling edge and injected microwave with different frequency or power. The simulation and experimental results agreed with each other very well, which means the Simulation Program with Integrated Circuit Emphasis (SPICE) models is effective in studying the microwave interference effects on CMOS digital circuits.Both of the simulation and experimental results shown that input logic levels(input high or low voltage)of cascaded CMOS inverter and the work voltage will affect threshold value of interference or reverse. Seen from the injected microwave power, between the inverter output voltage and injected power doesn't exist simple linear relationship, it is to say, with the increase of injected power the inverter logic level is not monotonically increasing or decreasing. Besides, the upset threshold power also depends on injected frequency. These findings can provides a good reference value for the study of high power microwave (HPM) interference effects towards the CMOS digital circuit devices and systems.