Differential current sensing scheme for magnetic random access memory

A circuit, comprising:

• an array segment;
• first and second reference columns,
• wherein
• each of the first and second reference columns comprises a plurality of reference cells, and
• the plurality of reference cells of the first and second reference columns store opposite logic values, respectively;
• and
• a current sense amplifier, configured with a first node and a second node for currents therethrough to be compared with each other,
• wherein
• the current sense amplifier comprises a multiplexer configured to
• couple the first reference column or the second reference column to the first node of the current sense amplifier, and couple the second reference column or the first reference column to the second node of the current sense amplifier in a first mode;
• and
• couple one column of the array segment to the first node of the current sense amplifier, and couple the first and second reference columns to the second node of the current sense amplifier in a second mode.

A method comprising:

• selectively coupling a first reference cell or a second reference cell to a first node of a current sense amplifier in a first mode;
• selectively coupling the second reference cell or the first reference cell to a second node of the current sense amplifier in the first mode;
• generating differential voltage outputs based on currents through the first and second nodes of the current sense amplifier in the first mode;
• selectively coupling a cell of a cell segment to the first node of the current sense amplifier in a second mode;
• selectively coupling first and second reference cells to the second node of the current sense amplifier in the second mode;
• and
• generating differential voltage outputs based on currents through the first and second nodes of the current sense amplifier in the second mode.