輸入欄位
- Length in mm
- Copper weight in oz
FPC / PCB 工程計算機
PCB 工程單位換算器：mm、mil、inch、um 與 oz 銅厚
換算 PCB / FPC 常用單位 mm、mil、inch、um 與 1oz 銅厚轉 um，適合圖面、疊構與 DFM 檢查。
工程單位換算器怎麼用
工程單位換算是 FPC / PCB 每天都會用到的小工具，特別是 mm、mil、inch、um 與 oz copper 在圖面、規格和工廠回覆中常常混用。
Engineering unit conversion is a daily PCB and FPC task. Drawings, customer specifications and factory replies often mix mm, mil, inch, micron and copper weight, including quick 1 oz to um conversion.
Common engineering conversions
公式: 1 inch = 25.4 mm, 1 mil = 0.001 inch, 1 oz copper = 34.79 um
- mm: millimeter.
- mil: one thousandth of an inch.
- oz copper: copper weight per square foot converted to nominal thickness.
公式依據
- Formula basis: SI length definitions, inch-to-millimeter conversion and common PCB copper-weight conversion; 1 oz copper is shown as about 34.79 um.
- Engineering note: copper oz values are nominal; use measured finished copper when tolerance matters.
範例
1 mm equals about 39.37 mil, and 1 oz copper equals about 34.79 um.
結果輸出
- mil
- inch
- um
- copper thickness
工程注意事項
- Always confirm whether mil means thousandth of an inch, not millimeter.
- Copper oz is a weight-based convention, often rounded to 35 um for quick communication.
- Use consistent units before comparing factory DFM limits.
驗證檢查
- Drawing unit review
- Stack-up conversion
- Copper thickness conversion
- Tolerance communication
相關製程站
- 材料選擇 - PI / PET / FR-4 thickness, RA or ED copper, adhesive type, coverlay thickness
- 疊構設計 - Total thickness, dielectric spacing, symmetry, controlled impedance
相關計算器
- 銅厚換算計算器 - oz / um / mil / mm 快速換算，含 base copper 與 plated copper。
- 疊構厚度與特徵繪圖工具 - 加總 PI、adhesive、copper、coverlay、stiffener，並繪製開蓋、Air Gap、通孔、埋孔與盲孔示意圖。
- 補強板 / ZIF 厚度匹配 - 估算 FPC、adhesive、stiffener 組合後厚度是否符合連接器規格。
FAQ
Is mil the same as mm?
No. In PCB/FPC engineering, mil usually means 0.001 inch, which is 0.0254 mm.
Why include copper oz here?
Copper weight is one of the most common unit conversions in stack-up and current calculations.