NC (Not Connected) Terminal of a Chip

Many times, chips such as op amps, have a NC terminal, which stands for Not Connected terminal.

This terminal should stay unconnected, meaning it should not be connected to your circuit at all.

Connecting the NC terminal to a circuit is not useful in any way, so it should always be left open.

Below is the pinout of a LM741 op amp chip, which contains a NC terminal.

So what is the NC terminal for?

NC terminals are created just for filler space. DIP chips are not made with an odd number of pins. The LM741 Op amp, for example, only has 7 useful pins. The 8th pin, the NC terminal, is created just so that there can be an even amount of pins. If a DIP chip had 7 pins, for example, placing it on a breadboard or an 8-pin IC socket would be much more difficult or impossible.

The NC pin is not even connected to the internal circuit of the chip. It is just an open wire.