US 8,009,458 B2 · Asymmetric write current compensation using gate overdrive for resistive sense memory cells

Abstract

Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element.

Claims20

Dependent claims

A method comprising:

providing a resistive sense memory (RSM) cell comprising a programmable RSM element and a switching device comprising respective gate, source and drain terminals, the source terminal connected in series to the RSM;
writing a first data state to the RSM element in a hard programming direction by sequentially applying a first voltage to the drain terminal and a second voltage greater than the first voltage to the gate terminal to flow a first write current through the memory cell with a first magnitude;
and
writing a second data state to the RSM element in an easy programming direction by applying the first voltage to the gate terminal to flow a second write current through the memory cell with a second magnitude nominally equal to the first magnitude.

1 more element

Dependencies are inferred from the claim text.

Asymmetric write current compensation using gate overdrive for resistive sense memory cells

Life of this patent

Asymmetric write current compensation using gate overdrive for resistive sense memory cells

Life of this patent

Abstract

Claims20