Patent ID: 7532063

Claim:
An apparatus for generating a reference voltage in a semiconductor memory apparatus, comprising: a first voltage generating unit configured to generate a voltage proportional to temperature; a second voltage generating unit configured to generate a voltage inversely proportional to temperature; a reference voltage generating unit including a first adjusting unit coupled with the first voltage generating unit and a second adjusting unit coupled with the second voltage generating unit, configured to select the first adjusting unit or the second adjusting unit according to a difference between a reference voltage obtained by the first voltage generating unit and the second voltage generating unit and a target voltage, and adjust the reference voltage thereby outputting a constant reference voltage regardless of a variation in temperature, wherein the reference voltage generating unit further comprises: a control unit configured to output selection signals for controlling the first adjusting unit and the second adjusting unit wherein the control unit includes: a selecting unit configured to output the selection signals for adjusting the amount of current in the first adjusting unit or the amount of current in the second adjusting unit by a predetermined level on the basis of first control signals; a first signal output unit configured to output the selection signals to the first adjusting unit or the second adjusting unit on the basis of a second control signal; a second signal output unit configured to output a first reference selection signal to the first adjusting unit on the basis of the first control signals and the second control signal; and a third signal output unit configured to output a second reference selection signal to the second adjusting unit on the basis of the first control signals and the second control signal; and a reference voltage output unit configured to output the reference voltage based on the amount of current adjusted by the first adjusting unit and the amount of current adjusted by the second adjusting unit.