The Research Of Time Parameter Measurement Unit For IC Test System

IC(Integrated Circuit) testing is an important component of the IC industry, and has an irreplaceable position in ensuring product performance and quality. The automated IC test equipment has become an indispensable tool for IC testing.Firstly, the various functional units and communication management mechanisms of IC test system were briefly summarized. The functional units of AC parameters measurement were mainly analyzed, and the referred key technologies and methods of the functional units were studied in detail. The hardware circuit, driver circuit and measuring instructions for users were implemented through the systems analysis of the functional units, and the testing function of design elements and measuring instructions was verified by experimental analysis.In the IC test system, AC parameter measurement function units are known as the time parameter measurement units(TMU). Digital converter(time-to-digital converter, TDC) is the key technology of TMU. A TDC circuit based on FPGA was represented. On the implementation of the TMU’s hardware circuit, hardware circuit measurement channel layout, the selection of components, functions plate voltage stability analysis, FPGA performance analysis, and circuit board signal integrity analysis were discussed. The circuit achieves time parameter measurement channels possessing four-way with high voltage testing ability and 16-way with low voltage testing ability. In the driver design of TMU, four types of logic circuit of time parameter measurement were designed, and the high resolution measurement of time parameters such as cycle, pulse width, rise / fall time was completed. By hardware circuit and driver circuit, the TMU reaches a predetermined time resolution of 2ns design goals.In the last part, a user-oriented time parameters instruction was achieved. IC tester can achieve the preparation of the test program, the view and processing of the test results on the visualized terminal. Meanwhile, the function of TMU were tested, and the measurement requirements were achieved.