PCBConnection method for implementing common use of single and double density in PCB test

Abstract

The invention discloses a connection method for achieving odd-density and even-density tests in PCB test, which comprises the following steps of: providing an even-density grid and an odd-density test channel group; averagely dividing the odd-density grid into a first region, a second region, a third region and a fourth region, so that the odd-numbered and even-numbered test point columns on the first region respectively sequentially correspond to the odd-numbered and even-numbered test point columns on the second region, and the odd-numbered and even-numbered test point columns on the third region respectively sequentially correspond to the odd-numbered and even-numbered test point columns on the fourth region; connecting the corresponding test point on the corresponding columns one by one; and connecting the connected two test points with one test channel in the odd-density test channel group. By connecting the even-density arranged grids with the odd-density arranged test channel group, the invention can achieve odd-density and even-density tests on a testing machine with an odd-density arranged test channel group, thus reducing the PCB test cost.

Description

【Technical field】 [0001] The invention belongs to the field of printed circuit board (Printed Circuit Board; PCB) testing, in particular to a method for connecting grids and test channel groups. 【Background technique】 [0002] According to the density of the distributed test points, the grids used in PCB general testing have different specifications such as single-density grids and double-density grids. Among them, the single-density grid has 100 test points per square inch, and two The distance between the test points is 100mil; the double-density grid has 200 test points per square inch, and the distance between two test points is 70mil. A common single-density testing machine is configured with a single-density grid and a single-density test channel group that matches it. The test points on the grid are connected to the test channels in the test channel group one by one, and one test point is connected to one test channel. , and in the existing test, the maximum slope of...

AI Technical Summary

Problems solved by technology

A common single-density testing machine is configured with a single-density grid and a single-density test channel group that matches it. The test points on the grid are connected to the test channels in the test channel group one by one, and one test point is connected to one test channel. , and in the existing test, the maximum slope of the needle can be 600mil, and the maximum density of the PCB that can be measured is 374 dots / square inch. The PCB that exceeds this density cannot be tested on a single-density testing machine, but must In addition, purchase a testing machine with a higher density—such as a double-density testing machine, a four-density testing machine, etc.—to carry out effective testing, which leads to an increase in the cost of PCB testing

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