US Patent 7471583 Memory device with self refresh cycle control function

Provided is a memory device capable of automatically controlling a self refresh cycle by sensing an ambient temperature, rather than setting Extended Mode Register Set (EMRS) code. The memory device includes a temperature sensing unit for generating a first voltage independent of a temperature variation and a second voltage dependent upon a temperature variation, a comparing unit for comparing the first voltage with the second voltage to provide a comparison result signal, and a self refresh signal generating unit for receiving a self refresh entry signal and generating a self refresh signal of temperature compensated cycle under the control of the comparison result signal.