Semiconductor memory device and method of generating chip enable signal thereof

Abstract

Provided are a semiconductor memory device and a method of generating a chip enable signal thereof. The device includes a plurality of memory chips and an interface chip that are stacked. Each of the memory chips includes a control signal setting unit, which sets input signals applied to first and second input nodes as less significant 2-bit control signals of n-bit control signals, performs a logic AND operation on the less significant 2-bit control signals to generate AND operated signals, performs a logic XOR operation on each of the AND operated signals and each bit signal of more significant n−2-bit input signals applied to third to n-th input nodes to set the n−2-bit control signals, outputs the signal applied to the second input node through a first output node, inverts the signal applied to the first input node to output the inverted signal through a second output node, and outputs the more significant n−2-bit input signals through third through n-th output nodes, respectively. The first through n-th output nodes of one of two adjacent memory chips are respectively connected to the first through n-th input nodes of the other of the two adjacent memory chips.