Integrated circuit memory devices having programmable output driver circuits therein

Abstract

Output drivers preferably contain a plurality of driver circuits therein that are commonly connected to an output line to be driven and can be selectively enabled or disabled to increase or decrease drive capability, respectively. Driver circuits may include first and second control signal lines (e.g., MRS , MRS ), a first pull-up/pull-down driver circuit having first and second data inputs, a first control input electrically coupled to the first control signal line (e.g., MRS ) and a second control input, and a second pull-up/pull-down driver circuit having first and second data inputs electrically coupled to the first and second data inputs of the first pull-up/pull-down driver circuit, respectively, a first control input electrically coupled to the second control signal line (e.g., MRS ) and a second control input. First and second complementary control signals lines (e.g., {overscore (MRS +L )}, {overscore (MRS +L )}) are also preferably provided and the second control inputs of the first pull-up/pull-down driver circuit and second pull-up/pull-down driver circuit are electrically coupled to the first and second complementary control signal lines, respectively. These control signal lines and complementary control signal lines can be used to control the number of driver circuits that are active within the output driver, based on loading conditions.