Patent ID: 7529135
Filing Date: 2009-05-05
Classification: G11C

Abstract:
1. An apparatus for controlling a bitline bias voltage, comprising: a detector for sensing the bitline bias voltage; a bitline bias control signal generation circuit coupled to the detector for generating a bitline bias control signal in accordance with the sensed bitline bias voltage; and a bitline bias voltage controller unit for controlling the bitline bias voltage in accordance with the bitline bias control signal, wherein the bitline bias control signal generation circuit includes a sensor for sensing the bitline bias control signal; a pull up circuit for pulling up the bitline bias control signal when the sensed bitline bias control signal indicates that the bitline is coupling low and that the sensed bitline bias control signal is less than a first reference value; and a pull down circuit for pulling down the bitline bias control signal when the sensed bitline bias control signal indicates that the bitline is coupling high and the sensed bitline bias control signal is greater than a second reference value.