Research On Remainder Detection Technique For Military Electronic Components Based On Random Vibration

Military electronic components are basic components which are essential for national defense system, and its reliability directly affects safety of the national defense electronic system. The remainder particles in the military electronic components reduce the reliability and become one of the main reasons affecting their reliability. Particle impact noise detection (PIND) test is an important method of detecting remainder particles, which has great significance of improving the reliability of the aerospace system. In the paper the method and technology for detecting particles in the military electronic components are researched and studied in order to make up for the shortage of PIND and enhance detection accuracy.This paper analyzes the research status at home and aboard and proposes test conditions based on random vibration which covers a wider frequency because it is difficult to identify the best vibration frequency for the traditional sine vibration test of PIND method. To improve the ability of PIND detection, acceleration spectrum, amplitude and frequency range are selected. For the questions of PIND and test condition concluded by intensive analysis, this paper puts forward the scheme design and technique parameters of the auto-detection system of military electronic components particles based on random vibration. Sine and random vibration waves are generated by DDS principle and the random vibration algorithm based on spectrum balancing of shaker transfer function is proposed to meet PIND experimental conditions.The technology of the direct digital synthesizer and means of push-pull tube drive are used to design the drive power circuits. Processing circuits of acoustic signal are designed to amplify and filter the signal remainder particles. Meantime, a calibration circuit is used to regulate the system precision, and protection circuits are to prevent the damage of both over-voltage and over-current to the shaker and power device. Adopting modular design and C program language, the procedure of particles detection is realized. At last, a type of aerospace relays and military transistors are tested under vibration and random vibration test conditions, respectively. The test results indicate that the system based on random vibration has better detection ability and high degree of automation, with above 90% of test accuracy.