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I am designing a PCB in EAGLE and I want to use an 7815 TO-220 voltage regulator. When I check the top or bottom layer mask of my PCB I can see that there is a hole (with no copper I think) behind the voltage regulator. Is this normal or I am using the wrong model?enter image description here

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    \$\begingroup\$ If the footprint is using an unplated hole for the TO-220 it might increase your manufacturing costs (if it's the only unplated hole). Looks like your mounting holes are also unplated. \$\endgroup\$ – Spehro Pefhany May 5 '15 at 15:26
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It's hard to tell from the spacing but that hole is likely there so you can screw the regulator to the board, or more likely mechanically attach a heatsink.

You can see an example:

enter image description here

If there was copper you'd run the risk of connecting the tab to a trace or an internal plane. This wouldn't work so well if your internal layer contained a power plane.

You should be able to find a vertical part in Eagle if you prefer the voltage regulator to remain upright.

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That is the normal mounting hole for a TO-220 package when mounted "lying down" on the board. If you are using a small heatsink, it would be placed between the regulator and board, and held in place, and in good contact with the regulator, by a screw through that hole.

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