An initial overdriven sense amplifier for low voltage DRAMs

Abstract

A high performance sense amplifier that provides a large initial driving current is proposed in this paper. In order to increase initial driving current of the conventional sense amplifier, the voltage levels of power sources are boosted by using a bootstrap technique. The sensing speed of the proposed sense amplifier is faster than that of the conventional one due to the large voltage difference between gate and source of the sensing transistor in the initial stage. The simulation result shows that a 5.6 ns (40%) sensing time is reduced compared to the conventional sense amplifier when the proposed sense amplifier is applied to sense data in 1.5 V supply voltage. In addition, the conventional sense amplifier fails to read data out in 1.3 V supply voltage whereas, the proposed sense amplifier still works under the same condition. These indicate that the proposed sense amplifier is suitable for application in low voltage DRAMs.