It is one of my first times creating a footprint. I have this BCT40T series DC/DC converter that has a THT footprint.
My question is... since it shows it as bottom view, does it mean I have to mirror it in the y axis while I create the footprint in my EDA?
Just for reference, I should end up with the second image that I provided correct? Why do they provide the bottom view anyways if it must be mirrored it after? I find it only confusing.
Welcome to the fun world of manufacturer datasheets and the difference between footprint data we want and what they provide!
First, note that the images you provided are from the Mechanical Details portion of the datasheet, which is not the same thing as footprint or "land pattern" (which you will see more often with SMT components):
It is common in component dimensional drawings to show various measurements as if you were examining the component on your bench (sans PCB).
Sometimes manufacturers will provide footprints in a separate document, such as if a JEDEC standard is used, but just as likely for arbitrary or proprietary designs. I looked around at XP Power's product page for more documentation or resources, but wasn't able to find anything referencing a recommended PCB layout.
In this case you just need to mentally transform dimensions and create the footprint accordingly (or as you did, flip the image if it helps). It's quite common, for example, for manufacturers to specify coordinates of SMT component pad edges, rather than center point. Depending on which PCB CAD software you use, you may find some presentations more helpful than others.
Yes, you need to mirror in Y or X axis to see how the footprint will look like.
You get the bottom view in CAD, because it is the image of the actual component, not the footprint it requires. If they showed a top view of the component, the pins would be hidden on the bottom side, so at least they would be marked as if you could look through the component.
Also if all other diagrams are from the actual component, it makes sense to provide the view of the bottom of the component as well, as it is exactly what you should see if you have the component in your hand and look at it from the bottom side where the pins are.
However, if they would show a footprint intended for the component, they would show it from the top side.
yes you'll have to mirror that if you want to install the converter on the top side of the PCB
