Final answer:
In a NAND gate, the voltage state is reversed from that of an AND gate by negating the output of the AND operation, resulting in the output being high (1) for all input combinations except when both inputs are high.
Step-by-step explanation:
In a NAND gate, the voltage state is reversed from that of an AND gate through the function of inverting the output. An AND gate performs a basic multiplication of input values where both inputs must be high (1) for the output to be high (1). Conversely, a NAND gate, which stands for NOT AND, takes the output of an AND gate and negates it. This means if the inputs to a NAND gate are both high (1), the output will be reversed to low (0), and for all other combinations of inputs, the output will be high (1). The NAND gate effectively implements logical negation following the AND operation, which can be likened to the semiconductor diode allowing current to flow freely in one direction and preventing it in the opposite, but the mechanisms for each are unrelated in terms of physical operation.