Dynamic random access memory circuit having a testing system and method to determine the sensitivity of a sense amplifier

摘要

A dynamic random access memory (DRAM) utilizes a testing system to independently control a voltage differential appearing between a pair of bit lines and sensed by the sense amplifier. The sensitivity of the sense amplifier is determined by monitoring an input/output signal in response to sensing the known voltage differential. The magnitude of the voltage differential appearing between the bit lines is controlled by enabling a first dummy cell to transfer a first reference charge onto a first bit line and by enabling a second dummy cell to transfer a second reference charge onto a second bit line.