PCB制作学习过程

从SparkFun上学习的，附上链接和视频截图
Using EAGLE: Board Layout

pcb界面、背景、网格设置

1.SparkFun在Github上下载的 spk.scr ，使用 PCB界面的颜 {MOD}有变化，看起来很舒服，如图所示

2.pcb和原理图背景设置为黑 {MOD}好看
3.网格显示开
4.电路图中电气连接属性的东东（Nets, Junctions and Nodes and Labels）
5.电路图功能分块（Truly expansive schematics should be split into functional blocks）
6.电路图中左边输入、右边输出（Really good schematic designers might even lay the circuit out like a book, inputs on the left side, outputs on the right.）
7.电路图中电压节点，做好颜 {MOD}标记，加外框显示等（Recognize Voltage Nodes）
8.随时查看器件手册**Reference Component **Datasheets

PCB制作过程

1.placing parts，器件位置，放好（飞线最好最少），确定板子的轮廓（尽量小，成本低）（板子小、过孔少最好）
2.(先弄敷铜到GND之后手动布线会容易一些)routing them（use the ROUTE tool）
3.generating gerber files to send to a fab house.

放置元器件考虑因素：

1.Don’t overlap parts: All of your components need some space to breathe. The green via holes need a good amount of clearance between them too. Remember those green rings are exposed copper on both sides of the board, if copper overlaps, streams will cross and short circuits will happen. 2.(RATSNEST按键)Minimize intersecting airwires: While you move parts, notice how the airwires move with them. Limiting criss-crossing airwires as much as you can will make routing much easier in the long run. While you’re relocating parts, hit the RATSNEST button – – to get the airwires to recalculate. 3.（比如去耦电容要挨着芯片、输入接口在电路板的边角等）Part placement requirements: Some parts may require special consideration during placement. For example, you’ll probably want the insertion point of the barrel jack connector to be facing the edge of the board. And make sure that decoupling capacitor is nice and close to the IC. 4.（紧凑）Tighter placement means a smaller and cheaper board, but it also makes routing harder.

PCB相关

1.**层**layers in EAGLE match up to the layers of a PCB

2.airwires：The gold lines, called airwires, connect between pins and reflect the net connections you made on the schematic.
3.GRID设置: 0.05 grid and 0.005” alternate grid is a good size for this kind of board.
4.板子外形Adjusting the Dimension Layer（20层、线宽0.008）set the layer to 20 Dimension

布线ROUTE 参数

1.（哪一层）Layer: On a 2-layer board like this, you’ll have to choose whether you want to start routing on the top (1) or bottom (16) layer.
2.（布线要45度弯曲）Bend Style: Usually you’ll want to use 45° angles for your routes (wire bend styles 1 and 3), but it can be fun to make loopy traces too.
3.（线宽设置）（ 线宽 默认0.01 电流大的话用线宽计算器 ）Width: This defines how wide your copper will be. Usually 0.01” is a good default size. You shouldn’t go any smaller than 0.007” (or you’ll probably end up paying extra). Wider traces can allow for more current to safely pass through. If you need to supply 1A through a trace, it’d need to be much wider (to find out how much, exactly, use a trace width calculator).
4.**（过孔）（过孔 默认圆形 0.02 自动添加过孔（换层或者鼠标中键））**Via Options: You can also set a few via characteristics here. The shape, diameter, and drill can be set, but usually the defaults (round, auto, and 0.02” respectively) are perfect.
5.(信号线之间的间隙)(信号线之间间距不能太小，默认0.006）Make sure you leave enough space between two different signal traces. PCB fabricators should have clearly defied minimum widths that they’ll allow between traces – probably around 0.006” for standard boards.
6.自动布线（Autorouter ）如果没时间的话再用，If it says anything other than “OptimizeN: 100% finished”, you’ve still got some work to do. If your autorouter couldn’t finish the job, try turning Routing Grid down from 50mil 10mil.EAGLE’s manual里面有自动布线的知识和优化方法。 7.布线完成时，按下RATSNEST icon – – and then immediately check the bottom left status box. If you’ve routed everything, it should say “Ratsnest: Nothing to do!” 说明所有的nets都连接好了
8.**（19层是未布线层）**19 Unrouted 9.没有飞线和DRC错误就可以生成gerber文件了
Once you’ve seen both “No airwires left!” and “DRC: No errors.”your board is ready to send to the fab house, which means it’s time to generate some gerber files.

RULE CHECK

RULE CHECK (the design rule check (DRC))（参考SparkFun的DRC设置文件SparkFun.dru） DRC Errors分类
1.Clearance: A trace is too close to either another trace or a via. You’ll probably have to nudge the trace around using the MOVE tool.
2.Overlap: Two different signal traces are overlapping each other. This will create a short if it’s not fixed. You might have to RIPUP one trace, and try routing it on the other side of the board. Or find a new way for it to reach its destination.
3.Dimension: A trace, pad, or via is intersecting with (or too close to) a dimension line. If this isn’t fixed that part of the board will just be cut off.

敷铜

敷铜Adding Copper Pours
铜一般弄成地信号Usually, when you’re adding a copper pour it’s for the ground signal.
1.POLYGON工具 （Isolate间隙设置成0.012）
2.设置net为GND
3.HIT ratsnest按钮 隐藏敷铜（use the RIPUP tool on the polygon border you just drew. Don’t worry, the polygon is still there, just hit ratsnest to bring it back.）
丝印Adding Silkscreen
silkscreen layer (tPlace for top, bPlace for bottom).

Generating Gerbers

Generating Gerbers（Gerbers 每一层对应一个gerber 加工需要7个gerbers）
Gerber files are kind of a “universal language” for PCB designs.
Gerber files – note the plurality – each describe single layers of the PCB.
In all, we’ll generate seven gerber files to send to the fab house.
CAM Processor
1.生成gerber文件
2.选择pcb生产商
3.发送Gerbers文件