PCB科技 - PCB設計的基本過程&佈局的基本原則和常識

基本流程 PCB設計& basic principles and common sense of layout
The general PCB設計 過程 is as follows:
Preliminary preparation - PCB structure design - net guide table - rule setting - PCB佈局-佈線-佈線優化和絲印-網絡和DRC檢查和結構檢查-輸出燈圖紙-燈圖紙審查- PCB板 生產 / 校對數據- PCB板 工廠工程EQ確認-補丁數據輸出-項目完成.
1: Preliminary preparation
This includes preparing package libraries and schematics. 繼續之前 PCB設計, 我們必須首先準備原理圖SCH的邏輯封裝和PCB的封裝庫. 套裝軟體庫可以是PAD附帶的庫, 但通常很難找到合適的. 最好根據所選設備的標準大小資訊自行構建套裝軟體庫. 原則上, 首先製作PCB封裝庫, 然後製作SCH邏輯包. PCB封裝庫要求高, 直接影響板的安裝； SCH邏輯封裝要求相對寬鬆, 只要注意引脚内容的定義以及與PCB封裝的對應關係. PS：注意標準庫中的隱藏管脚. 然後是原理圖的設計, 當它完成時, 已準備好啟動 PCB設計.

2: PCB structure design
In this step, 在中繪製PCB表面 PCB設計環境根據確定的電路板尺寸和各種機械定位, 並放置所需的接頭, 按鈕/開關, 螺釘孔, 裝配孔, 等. 根據定位要求. And fully consider and determine the wiring area and non-wiring area (such as how much area around the screw hole belongs to the non-wiring area).
3: Guide net table
It is recommended to import the board frame before the guide net table. Import DXF format frame or emn format frame
4: Rule setting
Reasonable rules can be set according to the specific PCB設計. 我們討論的規則是PAD的約束管理器. 通過約束管理器, 線寬和安全間距在設計過程中的任何環節都受到限制, 未滿足約束的情况. 後續DRC測試期間, 將使用DRC標記進行標記.
一般規則設定放在佈局之前，因為有時在佈局期間必須完成一些扇出工作. 因此, 必須在扇出之前設定規則. 當設計項目較大時, 可以更有效地完成設計.
備註：設定規則是為了更好更快地完成設計, 換言之，為了方便設計師.
The general settings are:
1. 默認線寬/普通訊號的行距.
2. Select and set vias
3. 重要訊號和電源的線寬和顏色設定.
4. 電路板圖層設定.
5: PCB佈局
The general layout is carried out according to the following principles:
(1) According to the reasonable division of electrical performance, it is generally divided into: digital circuit area (that is, afraid of interference and interference), analog circuit area (fear of interference), power drive area (interference source);
(2) Circuits that complete the same function should be placed as close as possible, 應調整組件，以確保最簡潔的連接； 同時, adjust the relative position between the functional blocks to make the connection between the functional blocks the most concise;
(3) For high-quality components, 應考慮安裝位置和安裝强度； 加熱部件應與溫度敏感部件分開放置, and heat convection measures should be considered when necessary;
(4) The I/O drive device should be as close as possible to the edge of the printed board and to the lead-out connector;
(5) The clock generator (such as crystal oscillator or clock oscillator) should be as close as possible to the device that uses the clock;
(6) Between the power input pin of each integrated circuit and the ground, a decoupling capacitor (generally a monolithic capacitor with good high-frequency performance is used); when the space of the circuit board is dense, 它也可用於多種集成電路. 在周圍添加鉭電容器.
(7) A discharge diode (1N4148 is sufficient) should be added to the relay coil;
(8) The layout requirements should be balanced, 密集有序, 而不是頭重腳輕.
需要特別注意. 放置零部件時, the actual size (occupied area and height) of the components and the relative position between the components must be considered to ensure the electrical performance of the circuit board and the feasibility and convenience of production and installation. 同時, 在確保上述原則得以體現的前提下, 應適當修改組件的位置，使其整潔美觀. 例如, 相同的部件應整齊地放置在同一方向上, 不應“分散”放置.
這一步與電路板的整體影像和下一步佈線的難度有關, 囙此，必須考慮一點努力. 佈局時, 您可以進行初步佈線，並充分考慮不確定的地方.
6: Wiring
Wiring is the most important process in the entire PCB設計. 這將直接影響 PCB板. 在 PCB設計流程, wiring generally has three realms:
The first is distribution, 這是 PCB設計 此時. 如果線路沒有連接，到處都是飛線, 這將是一個不合標準的委員會, 可以說你還沒有開始.