Townsend and Townsend and Crew LLP
Method for driving word lines in semiconductor memory device
 A method for driving word lines in a semiconductor memory device. A main row decoder generates a word line enable signal in s response to one part of address signal bits and a sub row decoder generates a word line boosting signal in response to the other part of the address signal bits. A bootstrap transistor transfers the word line enable signal from the main row decoder to a bootstrap node in response to a specific voltage. A high level voltage transfer transistor transfers the word line boosting signal from the sub row decoder to a corresponding one of the word lines in response to a voltage at the bootstrap node. After the word line enable signal from the main row decoder makes a low to high transition in level, the word line boosting signal from the sub row decoder is changed from a ground voltage level to a high voltage level to drive the corresponding word line. Then, the specific voltage is changed from the present level to the lower level. According to the present invention, the word line driving method can prevent a selected word line from floating due to OFF current resulting from a low level voltage at the bootstrap node when a row address strobe signal has a long duration. Furthermore, the word line driving method has the effect of enhancing the bootstrapping efficiency. 
Hyundai Electronics Industries Co., Ltd.
G G
G11C G11C
inventional inventional
Kee Woo Jung Pill
Park Kim