PCB News - Matters needing attention when drawing PCB schematic diagram

(1): When drawing the schematic diagram, the pin label must use the network NET, do not use the text TEXT. Otherwise, there will be problems when guiding the PCB board.

(2): After drawing, rename the components in order, select TOOLS-"ANNOTATE annotation and then select the order

(3): When drawing the schematic diagram, all components must be encapsulated, otherwise the components will not be found when guiding the PCB board. Some components cannot be found in the library. I have to draw by myself. In fact, I still need to draw by myself. After the drawing is done, you will have your own library at the end, which is convenient.

The drawing process is to start FILE/NEW--"Select SCH LIB--"This will enter the part editing library--"After drawing, press TOOLS-RENAME COMPONENT to rename the component.

The picture of the component package is the same as this one, but the PCB LIB is selected, and the border of the component is on the TOPOverlay layer, which is yellow.

(4): There is also the need to check the electrical rules: select TOOLS――.>ERC

(5): Then the PCB board can be generated. If there is an error in the generation process, the schematic diagram must be corrected to generate the PCB.

(6): Before converting into PCB, report should be generated, mainly net list. Select DESIGN design----》Create Netlist to create netlist

(7): The PCB must first be laid out well, and the line should be as short as possible, and the number of vias should be as few as possible.

(8): Design rules before drawing lines: TOOLS-Design Rules, GAP of Clearance Constrain in Routing can choose 10 or 12, set vias in ROUTING VIA STYLE, the maximum outer diameter of the Hanpan is the smallest The size of the outer diameter, the largest inner diameter, and the smallest inner diameter. Width Constraint sets the width of the line, maximum and minimum

(9): The width of the drawn line is generally 12MIL, the peripheral power and ground line is 120 or 100, the power and ground of the chip are 50 or 40 or 30, and the crystal line should be thick and placed next to the microcontroller. The public line should be thick, the long-distance line should be thick, the line cannot be turned at a right angle, and the line should be 45 degrees. The power supply, ground and other signs must be marked in the TOPLAY to facilitate the debugging of the connection. If you find that the diagram is incorrect, you must first modify the schematic diagram, and then use the schematic diagram to change the PCB.

The above is an introduction to the precautions when drawing PCB schematics. Ipcb is also provided to PCB manufacturers and PCB manufacturing technology.