An offset-cancelling four-phase voltage sense amplifier for resistive memories in 14nm CMOS

This paper presents a low-offset read sensing scheme for resistive memories. Due to increasing device variations in sub-32 nm CMOS processes, it becomes very challenging to design a high yield and low-offset read-sensing scheme. In this work we address these issues by using a pseudo-differential sensing scheme to get 2× signal margin and by full offset cancellation of the sense-amplifier, making it more suitable to tolerate variation from the memory array due to storage device resistance variation. Measurement results show the sense-amplifier can work with a 20mV input, which makes it ideal for small-signal sensing for resistive memories.