A device, comprising: a resistive change element array, wherein said resistive change element array comprises: a plurality of bit lines; a plurality of word lines; and a plurality of resistive change elements, wherein each resistive change element has a first terminal and a second terminal, and wherein said first terminal of each resistive change element is electrically connected to a bit line of said plurality of bit lines and said second terminal of each resistive change element is electrically connected to a word line of said plurality of word lines; a plurality of resistive reference elements, wherein each resistive reference element has a first terminal and a second terminal, wherein said first terminal of each resistive reference element is electrically connected to a bit line of said plurality of bit lines and said second terminal of each resistive reference element is electrically connected to a word line of said plurality of word lines, wherein said plurality of resistive reference elements comprises a plurality of low resistive reference elements and a plurality of high resistive reference elements, and wherein said plurality of low resistive reference elements have resistances less than resistances of said plurality of high resistive reference elements; a plurality of sense devices electrically connected to said resistive change element array; characterised in that the device further comprises: a circuit configured to sink an amount of current for an operation of at least one resistive change element in said plurality of resistive change elements based on a resistance selected by current flow between said circuit and said plurality of resistive reference elements, wherein said resistance is selected from at least two resistances, and wherein said circuit is electrically connected to said plurality of resistive change elements and said plurality of resistive reference elements. a resistive change element array, wherein said resistive change element array comprises: a plurality of bit lines; a plurality of word lines; and a plurality of resistive change elements, wherein each resistive change element has a first terminal and a second terminal, and wherein said first terminal of each resistive change element is electrically connected to a bit line of said plurality of bit lines and said second terminal of each resistive change element is electrically connected to a word line of said plurality of word lines; a plurality of bit lines; a plurality of word lines; and a plurality of resistive change elements, wherein each resistive change element has a first terminal and a second terminal, and wherein said first terminal of each resistive change element is electrically connected to a bit line of said plurality of bit lines and said second terminal of each resistive change element is electrically connected to a word line of said plurality of word lines; a plurality of resistive reference elements, wherein each resistive reference element has a first terminal and a second terminal, wherein said first terminal of each resistive reference element is electrically connected to a bit line of said plurality of bit lines and said second terminal of each resistive reference element is electrically connected to a word line of said plurality of word lines, wherein said plurality of resistive reference elements comprises a plurality of low resistive reference elements and a plurality of high resistive reference elements, and wherein said plurality of low resistive reference elements have resistances less than resistances of said plurality of high resistive reference elements; a plurality of sense devices electrically connected to said resistive change element array; characterised in that the device further comprises: a circuit configured to sink an amount of current for an operation of at least one resistive change element in said plurality of resistive change elements based on a resistance selected by current flow between said circuit and said plurality of resistive reference elements, wherein said resistance is selected from at least two resistances, and wherein said circuit is electrically connected to said plurality of resistive change elements and said plurality of resistive reference elements.