Seektronics

PCB board, mainly in order to make full use of the board, so as to improve production efficiency.   Relatively simple is the rule of the plate frame of the plate.     As shown in the picture above, the board frame is square, and it is easy to assemble four boards, among which, only one board needs wiring, while the other boards only need the frame, which the sample factory will handle (it is better to copy the components and lines in the past, so that it is not easy to make mistakes).   The lines in the mechanical layer of the regular plate frame are cut by the Vcut knife, but the plate thickness of 0.4mm cannot be cut by the Vcut knife.   What if it's an irregular frame?   In the picture above, stamp holes (with five circles) are used. I used a circle with a radius of 0.4mm and a line width of 0.127mm. The spacing between the circles is about 10mil, not too wide. In this way, the plate factory will drill holes in the rings, so that the hand can easily break it.   For the lines in

  Bare plate welding test procedure   1. After the circuit board is obtained, it is necessary to observe whether the circuit board circuit is damaged or not, and whether the welding plate is damaged or not.   2. Use a multimeter to measure whether there is short circuit between the power supply and the ground and between different power sources;   3, welding the first part of the power supply, and the power debugging successfully;   4. Weld the CPU and peripheral resistance, crystal oscillator and reset circuit again, and test the power supply and ground again after welding to avoid short circuit and thermal breakdown during welding;   Test after welding CPU: It is necessary to confirm that the crystal oscillator can start normally and reset normally. The program can be downloaded and simulated. When debugging, ensure that the corresponding IO port can be set.   IO port can be directly set to light the LED light.   5. Welding SDRAM and debugging.   6. Weld the serial port and connect i