So I am trying to assign footprints right now to all the components in my schematic. My schematic is all about a flyback converter. I have assigned footprints to most of the components such as resistors, capacitors (radial and rectangular throughholes), MOSFET (TO-247 package for example), and stuff. The only ones remaining that I haven't assigned footprints yet are the following: 1.) 2-pin terminal block (both on input and output) 2.) Holes for the transformer bobbin.

So my questions are: 1.) How do you assign footprint to a 2-pin terminal block? In my schematic, I used 1x2 CONN (connectors) for the two terminal blocks but when I am now assigning footprints via CvPcb, I can't seem to assign footprints to the terminal blocks well. What am I considering at this point is that, instead of using a 1x2 CONN on the schematic, I'd just place two 1x1 CONN instead, and assign individual wire-pads for each 1x1 CONN. And since I know that my terminal block pins has around 5mm distance, I'll just separate the two pads by 5mm on the PCB layout instead. Is this ok?

2.) Basically, same problem as the first one but instead this time, I want to assign holes for the transformer bobbin that I will be using. In my case, the bobbin that I will use is for the PQ26/20 transformer core that I will be using. The mechanical details of the bobbin is shown below.

Fig.1 Bobbin Mechanical Details Bobbin mechanical details

Since I know that separation distance between the bobbin pins, what I am thinking for the transformer footprint is that I'd do the same as in 1. Assign 1x1 CONN in the schematic for each bobbin pin I'll be using (transformer winding-pins). Then in footprint, assign wire-pads individually. Then on PCBlay-out, I'll just place the wire-pads based on the mechanical data that I have. Is this ok?

For extra info, a part of my schematic is shown below for the terminal blocks (CONN) and transformer core that I want. Right now, in my schematic, I placed a transformer as is, instead of six 1x1 CONN for each transformer pin. To avoid confusion, the two 1x1 CONN (P3 and P4) in the schematic are just for the fuse that I'll be using.

Fig. 2 Input Terminal Blocks Input Terminal Blocks

Fig. 3 Transformer (bobbin pins) and Output Terminal Blocks Transformer and Output Terminal Blocks

Fig. 4 1-2mm wire-pad that I am considering on using enter image description here

  • 3
    \$\begingroup\$ You should make a proper footprint for the coil. Anything else is asking for pain and tears. \$\endgroup\$
    – JRE
    Mar 6, 2018 at 12:22
  • 1
    \$\begingroup\$ I second that, I was about to ask why you just don't create the footprints yourself. Granted, it takes time but is usually worth the effort, if you don't find a fitting one. \$\endgroup\$
    – koalag
    Mar 6, 2018 at 12:26
  • 2
    \$\begingroup\$ You strategy with 1x1 connectors is EXTREMELY BAD idea. Creating custom footprints is not that hard and is inevitable in a proper layout. Here are some videos that might give you some insights: 1, 2 \$\endgroup\$ Mar 6, 2018 at 14:32


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