Hi there. So far we have seen and learned how we can create a single sided PCB in Eagle, we have created one power supply socket as well as we have created a microcontroller base socket. Along with that, I have also given you a number of different sockets for experimenting with the single sided PCB design. And now let's start with double sided PCB design with Eagle. So, let's begin. So, double sided PCB as we have seen in the very first basics lecture is the same size of PCB or same kind of PCB like single sided one, the only difference is it has a positive position on both sides of the substrate.

So, there is a substrate and there is a copper from top side as well as there is a copper from bottom side. The benefit is first benefit is you can insert components from both the sides so you can insert component from here and so on. Here are insert component from here and then solder it here then you can use surface mounting components on top as well as the carrier surface mounting components on bottom. Although we can do these in general practice it is recommended to place all your components on one side let that be true all or let that be assembly. So which a single sided PCB if I'm using surface mounting components, then component comes like this suitors here and surface mounting component saves here, but in double sided PCB, you can have it on the same side. Of course, in certain cases, if needed components are placed on both sides.

So let's see how we can create PCB with this. What happens is you create some particular track on this layer. And then what you can do is you can just make a hole between the substrate a plated hole a plated with metal and then this top layer can get connected to the bottom layer. And thereby it gives us chances to create number of different Types of circuit tracks. Let's see. So double sided PCB is something where copper tracks are present on both sides components may or may not be present on both sides, top and bottom layer.

These are the two layers we used. top layer generally in almost every designing software is colored standard as red and bottom layer tracks are layered as blue. And that's the reason why so far we have created some PCBs and that's why we have seen the track color is blue. The default view on Eagle or how we look at the PCB is always top or top side of you. So this is how the PCB looked like after the manufacture and that's why whatever we are looking at it from top to top silk is basically this diode and led and these kind of letters but it's called as a top selfie. You always look at it from the top set And when looking at from the top side, you This is the tracks present on bottom left, you'll never see the tracks on the top layer and whenever you have a track on the top layer it will appear red like this.

So this was a jumper we placed in last session and how we connect this bottom track and how we connect is this track on the top side is using a very small hole lesser than the ISIS dribble. And it's just solders via via is basically a hole and this creates a connection between top and bottom layer so it's a hole connecting top and bottom layer. It creates an interconnection between the two layers and it is most important to understand why doing double sided design. So a hole is made and it is poured with a conductive metal which makes it sub PPH on printed through whole there right it can correct me topless Or the track coming from the top layer, the cracks going on in the bottom layer. So let's start creating our PCB with double sided technic. Let's create the same microcontroller sockets, and instead of routing it completely using a bottom side or the bottom copper layer, let's try to use the top layer as soon as the bottom layer and with next video, we'll see how we can create the same socket in double sided way and then we'll see a smaller socket which we can fit into a much lesser size so that the double sided PCB is just repaired.

Generally double sided PCB design technique is used to reduce this space. And that's why we have to have a circuit which is complex enough which is to be fixed into small pieces, then we can use the double sided PCB designing technique. Moreover, double sided is a standard way now there is not very big difference in single sided and double sided PCB design and that's why a designer will prefer if tracks are not routed. On one side and they will prefer to reduce the size and routed on both the size. So let's get started. Thanks for watching this video.