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Portability and low cost make the PXIe system the best choice to reduce the cost of integrated circuit(IC) testing. However, due to the limitation of the PXIe module volume, the number of channels in a single module cannot be enough. And the testing of an IC with more pins will require multiple modules to achieve. In general, the synchronization performance between channels will be one of the most important indicators which affect the test capability of an IC test system. In this paper, a method which based on calibration to achieve synchronization between test channels in the IC test system is proposed. Through testing, toe time delay between board-level channels is

The generation of high-speed digital vector is one of the main problems in IC testing. With the increasing of the working frequency of digital circuits, the speed and accuracy of digital test vector are also required to be higher and higher. Based on FPGA high-speed transceiver, this paper provides a method of generating high-speed digital integrated circuit test vectors. It also introduces the specific implementation of high-speed digital pattern synthesis and broadening, and explains the possible situations in it. The resulting test vector speed is up to 800Mbps and the edge positioning accuracy can reach 40ps.

Camera calibration is the first and the most important step of spatial position measurement. Aiming at improving the measurement precision over a large field of view and long distance, the internal and external parameters of the camera need to be calibrated accurately. Therefore, a simple and accurate calibration method is proposed to solve the problem that a small calibration board cannot appear in the field of view of multiple cameras at the same time. We calibrate the internal and external parameters of camera separately. For the internal parameters, we calculate it using analytical solution estimation method after collecting calibration plate images for feature point detection. For the external parameters, we accurately obtain the relative positions of the cameras with the help of the total station, and then unify the pose relationship of each camera to the same coordinate system through rigid body transformation to obtain the parameters. Then, the maximum likelihood method is used to optimize the estimation of both internal and external parameters to improve the calibration accuracy. Finally, the three-dimensional coordinates of target can be obtained by triangulation. The experimental results show that this method meets requirement of calibration accuracy, and the error of the 3D spatial position of the target is in the centimeter level.