Method of bed test
This method is called by the spring-loaded probe connects to the circuit board on each point. Springs makes each probe has a 100-200g pressure to ensure good contact of each detection point, such probes are arranged together are known as "needle bed". Under the control of test software and test points and test signals can be programmed, Figure 14-3 is a typical structure of needle bed Tester, testing can find out information on all test points. Need to test only those test points of the probe is installed. Despite the use of needle bar test method may be tested simultaneously on both sides of the circuit board, when a circuit is designed, or should we all point at welding surface of the circuit board. Bed Tester equipment expensive and difficult to repair. Needle probe arranged according to their different specific applications.
A basic common grid processor from a bored Board composition, its PIN on Center spacing is 100, 75 or 50mil. Pin up of interaction, and electrical connections on the circuit board or a direct mechanical connection between the nodes. If the pads on the circuit board and test grid to match, then in accordance with perforated polyester film is placed in a grid between the circuit board and, in order to design specific probes. Continuity test is through the end of the access grid point (coordinates has been defined as the x-y pad) implementation. Since each network continuity on the circuit board testing. In this way, an independent inspection is completed. However, how close the probe limits the effectiveness of needle bar test.