SEMICONDUCTOR MEMORY DEVICE BEING CAPABLE OF TESTING HIGH FREQUENCY CIRCUIT IN WAFER STATE

摘要

A semiconductor memory device is provided to test a high frequency circuit in a wafer state, by changing a multiplication mode of a phase locked loop circuit into an x1 mode in response to a test signal. In a semiconductor memory device in a wafer state, a high frequency circuit receives a test clock from a wafer test apparatus(210). A mode register(223) receives a test signal from the wafer test apparatus, and changes a multiplication mode of the high frequency circuit so that the high frequency circuit is operated in response to the test clock. The high frequency circuit is a delay locked loop circuit.