Effect of printed circuit board size on throughflow

We first calculate the hole carrying capacity with a tool, or adopt the revised specification of IPC2152.

The protection thickness of copper plating is generally 0.8mil to 1mil according to IPC2 or IPC3 standards. 1oz vs 2oz My original plan was to use 0.8mil with a smaller range. Last Friday and Saturday's high-speed through Mr. Education training, a friend can put forward a limit working situation, through the hole wall of the copper plating thickness and may appear wide up and down, narrow in the middle, so the narrowest place development limit problem may be 0.7mil.

Although I think the sheet mill is good, or at least to meet 0.8 meters of hole wall copper thickness. how to test a circuit board with a multimeter However, in this article, I decided to take my friend's advice and evaluate the hole wall copper thickness to a worst-case scenario of 0.7 m. Our technology Mr. Dongge has been rubbing his hands, next is his article about plating thickness, will discuss the thickness of the surface plated copper foil and the thickness of the hole wall plated copper, please look forward to.

Some of my analysis:

The 1.12mil hole can safely carry a current of about 1.2A, which is looser than the 0.5A generally recognized by the industry;

The larger 16mm, 20mm or even 24mm holes do not have a clear current-carrying advantage, and many argue that this is not linear growth.

Therefore, I personally recommend using 10~12mil holes to carry current, which is more efficient and convenient in design. So, did you know that this via carries current data, and then you can design it safely? Let's look at some simulations:

20A current, played 20 12mil through the hole, according to our each hole bearing 1.2A calculation, feel very important and safe. But they are actually currents that are not as obedient as you might think, and are not distributed evenly across 20 holes. Simple DC simulation, you can see through the hole current situation. Some of them are running at 2.4A, some are running at 200mA. Of course, this problem during the design process may lead to final development and does not necessarily have much impact on the risk. Because the 12mil hole can be used to carry more than 2A working current when the temperature rises by 30 degrees. But what if the inhomogeneity is further amplified? This is the channel with your AC current, the distribution and quantity of the holes have a relationship, what if a certain hole takes 3A or even 4A current? And the enterprise at this time you punch 25 or 30 holes, as long as the students are not in the key location of the current, the help provided to people will not be very large. The reason is the same: electricity and not as obedient as you think.

This conclusion is also effective for determining the width of copper plates. We can find from many simulation results that when the high current design is not enough in one layer of copper, the current walking in another layer will not be evenly distributed. Because the article is too long, can not put too many cases, if you are interested, you can contact Mr., as long as more people reply, we can add an article to discuss this issue.

When the current reaches the order of more than 20A, the conventional copper-coated current carrier and the through hole current carrier calculated by experience or formula have risks. The most effective way to do this is through DC simulation software.

revised specification linear growth

0