DATA OUTPUT BUFFER OF SEMICONDUCTOR MEMORY DEVICE CONTROLLED BY MODE REGISTER

摘要

PURPOSE: A data output buffer of a semiconductor memory device is provided to be controlled by a mode register and improves an output current variation within the noise margin limit. CONSTITUTION: The device includes a mode register(100) comprising: an output stage outputting an output signal responding to an input signal; a pull up driver to pull up-drive the output stage in response to the input signal; a number of pull down drivers which pull down-drive the output stage in response to the input signal, and are connected to the output stage in parallel; and a selection unit transfers the input signal to at least one pull down driver in response to a control signal, in order to enable at least one pull down driver selectively. Thus, the data output buffer adjusts the output current variation to have minimum variation within the noise margin limit with a simple method.