The following will introduce the thickness of copper in heavy copper pcb.Standard computer circuit boards, whether double-sided or multilayer, are manufactured employing a combination of copper etching and plating processes. Circuit layers start as thin sheets of copper foil (generally 0.5 oz/ft2 to 2 oz/ft2) that are etched to get rid of unwanted copper, and plated to feature copper thickness to planes, traces, pads and plated-through-holes. All of the circuit layers are laminated into an entire package using an epoxy-based substrate, like FR4 or polyimide.
Boards incorporating heavy copper circuits are produced in just an equivalent way, albeit with specialized etching and plating techniques, like high-speed/step plating and differential etching. Historically, heavy copper features were formed entirely by etching thick copper clad laminated board material, causing uneven trace sidewalls and unacceptable undercutting. Advances in plating technology have allowed heavy copper features to be formed with a mixture of plating and etching, leading to straight sidewalls and negligible undercut.
Plating of an important copper circuit enables the board fabricator to extend the quantity of copper thickness in plated holes and via sidewalls. It’s now possible to combine heavy copper with standard features on one board, also referred to as PowerLink. Advantages include reduced layer count, low impedance power distribution, smaller footprints and potential cost savings. Normally, high-current/high-power circuits and their control circuits were produced separately on separate boards. Heavy copper plating makes it possible to integrate high-current circuits and control circuits to understand a highly dense yet simple board structure.
Current Carrying Capacity and Temperature Rise
The amount of current a copper circuit can safely carry depends on what proportion heat rise a project can withstand, since heat rise and current flow are related. When current flows along a trace, there’s an I2R (power loss) that leads to localized heating. The trace cools by conduction (into neighboring materials) and convection (into the environment). Therefore, to seek out the utmost current a trace can safely carry, we must find how to estimate the warmth rise related to the applied current. a perfect situation would be to succeed in a stable operating temperature where the speed of heating equals the speed of cooling. An IPC formula are often wont to model this event.