Memristance drift avoidance with charge bouncing for memristor-based nonvolatile memories

A charge-bouncing solution to avoid the undesirable drift in a programmed memory during readout of a memristor-based non-volatile memory is proposed. A memristor memory can be programmed by using strong programming signals, and the programmed memristance can be readout by using weak readout signals. Though readout signals are weak compared to programming signals, the readout charge accumulates over time, leading to an undesirable drift of the operating point. This causes an error in the programmed memory. Memristance drift is an important problem for practical utilization of memristors as memories. The only way presented so far to avoid such a drift is by converting input signals to doublets, but non-ideal doublet signals still cause drift problems. In the proposed method, drift is avoided using a capacitor in such a way that all the charge injected into the memristor during readout is stored in the capacitor and bounced back through the memristor after the readout has been completed. Experimental results showing an excellent recovery from the temporal memristance drift when using singlet pulses rather than the conventionally-used doublet pulses for memristive memory readout are also presented.