Labs: LTspice NAND gates
The AND/NAND gate in LTspice is an odd part. Here is the URL to a website explaining it:
https://www.electronicspoint.com/resources/going-digital.19 Links to an external site.
Note that all unused inputs have to be connected to pin 8, and pin 8 must be connected to the system gnd.
Also, you need to use the Component Attribute Editor to set the Vhigh = logic 1 voltage (5V) and the level (ref=2.5) at which an input is considered to be a 1 instead of a 0. The power supply voltage is taken to be the same as Vhigh.
Here is a screen shot of how it can be hooked up as a 2-input NAND gate: