How do you calculate current carrying capacity of PCB traces?
Max Current You can calculate maximum current by using the formula A = (T x W x 1.378 [mils/oz/ft2]). The values in this formula correspond with the following parameters: A: Cross-section area.
What is copper trace?
When it comes to creating printed circuit boards, engineers often guestimate various aspects of their design. One such design metric is known colloquially as Trace and Space. Trace refers to the width of a particular copper track, and Space refers to the width of the gap between two adjacent pieces of copper.
How do you determine trace width?
The important characteristics to consider when selecting a trace width include:
- The current capacity of the trace (how much current will flow through it)
- The allowable spacing between traces.
- The size and pitch of the pads that the trace will be connecting to.
What is 2 oz copper PCB?
2 oz copper (70µm thick or 2.8 mils) — Standard internal layer copper thickness for internal layers on 3 oz finished copper selection. This is the standard starting copper thickness on the external layers for PCBs with the 3 oz finished copper weight selection.
How much copper is in a PCB?
Introduction. Printed circuit boards (PCBs) are essential parts of the great majority of electric and electronic devices, which can contain more than 18% Cu, 80 g ton−1 Au and 600 g ton−1 Ag.
Why is copper used for PCBs?
Why is copper such a popular choice in the PCB industry? The number one benefit of copper is that it is highly conductive. This means that it can easily transmit signals without losing electricity along the way. It also means that manufacturers don’t have to use tons of copper.
What is a typical minimum width for a copper track?
Inner layers
| Copper thickness | min. conductor trace width / space | |
|---|---|---|
| Copper thickness | 12µm | 75µm/100µm** |
| Copper thickness | 18µm | 90µm |
| Copper thickness | 35µm | 100µm |
| Copper thickness | 70µm | 150µm |
How thick is the copper on a PCB?
How is the carrying capacity of copper determined?
Relationship between Copper Weight, Trace Width and Current Carrying Capacity. Theoretically, PCB (Printed Circuit Board) current carrying capacity is determined by cross-sectional area of trace and temperature rise. Furthermore, cross-sectional area of trace is directly proportional to trace width and copper thickness.
How much current can a copper trace carry?
Mathematically speaking, the capability of trace to carry current is directly proportional to the cross sectional area of trace and temperature rise. As can be seen from the table below, that under the temperature conditions of 20 O C, a trace width of 10mil with 1.0 oz of copper can withstand 1.2A current.
What is the relationship between trace width and carrying capacity?
A current table is essential to understanding the relationship between the PCB trace width and the current carrying capacity. This relationship enables you to determine the trace width needed for your PCB. The current carrying capacity is the maximum current that can run through the trace without exceeding the top temperature rating.
What’s the relationship between Copper thickness and trace width?
There is a direct relationship between the trace width and the current carrying capacity of your board. If there is a cross-sectional area of trace and temperature rise, that will determine your current carrying capacity. The cross-sectional area of trace is directly relational to the copper thickness and trace width.
