SN74CB3Q3245: NC and thermal pad connection

It does not matter what you do with the NC pin.

The thermal pad can be left floating or be connected to ground; see [FAQ] Where do I connect the thermal pad of the logic QFN devices?

In addition to what Clemens said the NC pin is electrically not connected to device and doesn't not have any effect on device operation.

Regards,

kameron

In lower-frequency applications, unused bus pins may be left floating. For higher-frequency applications, it is advised to tie these unused inputs to GND through a termination resistor (about 50 Ω). See [FAQ] What to do with Unused Pins & Exposed Thermal Pads?

Hello Kei,

I agree with Clemens on this.

Please let us know if you have any further questions!