Based On The The Qfn Package Class D Audio Amplifier Testing

Testing is to delete design bad product to avoid both the time and cost waste if directly application on Pcb., for consumer electronic products it is indispensable. With the continuous improvement of the performance, in the chip from wafer to finished products in the process, the technology level also needs further improve, testing as a final and very key step must also get corresponding improvement. Different from other package form of testing, a device based on QFN package has its unique test method.This topic is from Shanghai Chiphomer microelectronics Crop. they full entrust SMIC to do the assembly and test for their device CP2230QN which designed by themselves. For the testing, request to design and develop all the hardware and software, and need to mass production. Product test engineering department will finish all the design of hardware and software,then base on software and hardware to debug test parameter,until this device put into mass production smoothly. Main job include the following aspects:1.Used kelvin test with four line,used convenient Altium Design tool to complet the test circuit board Design and production, including test Principle drawing and test circuit wiring, the board and to be processing.2.The sourse boards of AST2000 tester system are studied in detail and sourse boardapplication is investigated in detail in the debugging3.The product datasheet and test specification are investigated in detail, the test principle and test method for every test parameters are studied, also the effects of test sequence is considered in detail4.The issues and solutions in debugging are analysed in detail.5.The data differentces between theoretics and practice are analysed in detail, also the importance of data consistency and repetition in mass production are analysed in detail.In the meantime emphatically resolve the actual test circuit interference, bad shielding, the contact problem,the unstable value of test parameters and bad precision , especially in the test parameters such as THD are particularly outstanding. The smooth completion of the project design, guarantee the products in quantity during parameters of no more than 2% difference, and ensure high quality products performance at the same time, improve product test yield, let the customer's products better and faster more invest to market, supply the fast growth of market demand.