I've been looking at my scope's power supply board and I noticed that R7731A "Burst Triple Mode PWM Flyback Controller" in DIP has two NC pins which are not connected to absolutely anything. They've been inserted into holes, but there are no matching pads on the solder side.
On the other hand, in various other devices I've seen components with NC pins which are soldered to a pad, but the pad is not connected to anything else.
So my question is: What's the benefit of not using solder pads for NC pins?
Best Answer
When you solder to a pad -
Pro: -It is mechanically stronger
Con: -You will likely have a very, very minor increase in noise inside of the device, negligible in all but the most extreme situations (which you wouldn't be using a plastic device with NC pins anyway)
-You increase build time slightly and you also increase the risk of a solder short (or other process errors)
Anyway, I usually put a non connected pad there just in case I want to change ICs and wire a jumper wire over or something like that.