Design And Implementation Of GaN Power Device Automatic Test System

With the advantages of high voltage, high temperature resistance, radiation resistance, corrosion resistance, high thermal conductivity, wide band gap and large electron drift velocity etc, the gallium nitride(GaN) semiconductor material wide band gap, has rapidly become the third generation of new semiconductor materials at present. This material is suitable for high frequency and efficient production of high-power devices at high temperature and high voltage and environmental work. GaN devices automatic test system was based on an existing platform. It had been designed GaN packaged devices automatic test system(ATS) to enhance testing capabilities and testing efficiency. Owing to the multiple testing parameters and the high level parameters of GaN high-power microwave devices, we had developed the highly integrated intelligent automatic test system which was based on the existing testing equipments and the new signal routing unit. This aimed to provide testing technical support which would help us to reflect devices performance level truly and to enhance the efficiency of devices testing greatly.This test system hardware part used industrial personal computer(IPC) as the controlling center. It used standard instrument bus and interface to build a flexible automatic test system by test development management software platform and test methods set. The system consisted of automatic test equipments, the signal processing and distribution channels. Firstly, the hardware block diagram of the test system is built. Then the entire spectrum is used to obtain higher accuracy in-depth study of the phenomenon of desensitization traditional pulse testing. The minimum mean square algorithm and the time domain envelope convolution algorithm are used to reduce the desensitization phenomenon. At the same time, the parameters of the device are verified, and the feasibility of the hardware of the testing system is ensured.This test system software used layered open architecture design. Different levels of functional modules were isolated. It provided a single data interface for information exchange and sharing. According to the level, the whole software from the bottom to the upper layer can be divided into three layers, the driver layer, the functional layer and the interaction layer. In this way, the system met the principles of high cohesion and low coupling. Single connect multiple measurement(SCMM) technology is used in this test. In order to complete the test with fewer hardware resources and to minimize the human factors like device connection, wear, etc as far as possible. The test apparatus and equipment in the system are not directly connected with the unit. The connector is connected to the test resources(module and apparatus), and the adapter is connected to the test unit. The adapter can accomplish the function of the signal attenuation / gain and the electronic load with internal signal conditioning circuit. It can accomplish the assignment of the signal and the signal channel of the test resource by switching matrix, at the same time, it can test resource configuration and build signal route.