Semiconductor memory device capable of switching from multiplex method to non-multiplex method

Abstract

An address pad is independently provided to receive only the address signals independently from an address data multi-pad into which the address signals and the data signals are inputted. The path of the address signals to be inputted to an address buffer is switched by a switching control signal generated in the multiplex system / non-multiplex system. Thus, the address signals and the data signals can respectively be inputted to the address buffer and a data buffer 35 in parallel.

Description

technical field [0001] The present invention relates to a semiconductor memory device, and more specifically, to a semiconductor memory device capable of switching whether or not to use a multiplexing method. Background technique [0002] In recent years, the miniaturization and high integration technology of semiconductor integrated circuits has progressed rapidly, and the increase in capacity and scale of memory devices has been remarkable. Along with this, the number of bits to be processed also increases, and therefore, the number of terminals required for address terminals, data input / output terminals, and the like also tends to increase. [0003] Conventionally, for example, a method of preventing an increase in the number of terminals by sharing terminals in a multiplexing system has been employed. [0004] JP-A-11-306796 discloses an address multiplexing method, and discloses a semiconductor memory device in which address terminals are time-divisionally shared on th...

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Problems solved by technology

[0006] However, when a semiconductor memory device using a multiplexing method that realizes the sharing of address terminals and data input and output terminals described in this publication is used, even if the terminals are shared, the types of information processed, address signals and data signals are completely different, such as wafer testing. When testing this semiconductor storage device in a test machine, compared with a conventional semiconductor storage device that is not a multiplexing method (hereinafter also referred to as a non-multiplexing method), the external command system becomes very complicated. Completely different test procedures and test fixtures for multiplexed semiconductor memory devices

That is, a tester for a non-multiplexing method, which is a conventional semiconductor storage device, cannot be used, and the tester for this method is very expensive, causing a problem that the test cost increases significantly.

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