PCB News - Copper platinum thickness, line width and current relationship

1. PCB current and line width

The calculation of PCB current carrying capacity has always lacked authoritative technical methods and formulas. The experienced CAD engineers can make more accurate judgments relying on personal experience. But for CAD novices, it can be said that they have encountered a problem.

The current carrying capacity of PCB board depends on the following factors: line width, line thickness (copper foil thickness), and allowable temperature rise. Everyone knows that the wider the PCB trace, the greater the current-carrying capacity. Assuming that under the same conditions, a 10MIL trace can withstand 1A, how much current can a 50MIL trace withstand, is it 5A? The answer is naturally no. Please look at the following data from international authorities:
The unit of line width is: Inch (1inch=2.54cm=25.4mm)

Trace Carrying capacity per mil std 275

2. PCB design copper platinum thickness, line width and current relationship

Before understanding the relationship between PCB design copper platinum thickness, line width and current, let us first understand the conversion between ounces, inches and millimeters of PCB copper thickness: "In many data sheets, PCB copper thickness is often used in ounces. As a unit, its conversion relationship with inches and millimeters is as follows:
1 ounce = 0.0014 inches = 0.0356 millimeters (mm)
2 ounces = 0.0028 inches = 0.0712 millimeters (mm)

Ounce is the unit of weight, and the reason why it can be converted to millimeters is because the thickness of the copper coating of the PCB is ounces/square inch"

PCB design copper platinum thickness, line width and current relationship table