The Difference Between 2L MCPCB and Double Sided MCPCB

In our last article, we know what a metal core PCB is, in this post, we will introduce what is the difference between 2L MCPCB and Double sided MCPCB. Please continue to read if you want to know more about metal core printed circuit board.

Today we will explain from these four contents as following:

Stack up (structure)
Heat dissipation
SMD populate
Manufacturing technology

Stack up of 2L MCPCB and Double Sided MCPCB

For a 2L MCPCB, the metal core is positioning on the bottom side of the MCPCB as a cooling carrier to the whole MCPCB, while the metal base of double sided MCPCB is located in the middle of two copper trace. In generally, some PTH (plated-through-hole) vias are needed to designed to connect the bottom and top traces.

Below are the stack ups of these two kinds of products, from the structure, we can easily distinguish which one is 2L MCPCB and which one is double sided MCPCB.

Heat dissipation of 2L MCPCB and Double Sided MCPCB

Due to the different structure of the two products, their heat dissipation performance is also different. The main reason is the heating of double-sided metal core circuits can be spread out through both top and bottom side, while the heating generate by SMD components of 2 layers circuit only can be dissipated through bottom (metal) side and the heat need to go down layer by layer. In addition to this, the dissipation of FR4 is not good than metal materials, so double-sided metal core printed circuits perform better heat dissipation performance than 2 layers MCPCB.

Surface mounted locations (SMD populate)

Nowadays, surface mounted technology (SMT) is widely used in printed circuit board industry, more and more designers prefer to populate electronic components of the circuit surface to achieve high density, stable electrical performance and high reliability. 2L metal core circuit boards and double-sided metal core circuits also show their different mounted locations in this aspect.

The populate location of a 2L MCPCB only available on copper trace side, that is top side. And a double-sided metal core PCB can mount components on both top and bottom side, because both of them exist copper trace on it.

Manufacturing technology

May somebody will curious about “Are these two products produced in the same process/technology?”

The answer is obvious “NO, they have a different laminate process when fabricating.”

Different with single layer MCPCB, double sided MCPCB requires an additional pressing step to laminate the thermal conductive layer and metal core together. But sometimes, some raw Metal Clad material vendor will supply board material which already laminated.

For 2 layers metal core PCB, due to it is made of a single MCPCB and a double-sided FR4 PCB, the first thing we should make a double sided FR4 PCB, then laminate the PCB together with the single MCPCB. But due to the thermal conductive layer (pure adhesive) is easy to overflow during laminating process, which will cause the poor adhesion and crack between metal core and FR4 PCB. In the meantime, to avoid such problem, an experienced operator is needed to proceed the laminated process. That is why the lead time and cost of a 2 layers metal core circuit is much longer and expensive.

This is the end of this post, if you still have some questions or difficulties about the metal core PCB, welcome to contact us at sales@bestpcbs.com, our professional sales team and engineering team will give you a best solution for free.