Sensing the state of a storage cell including a magnetic element

A system comprising:

• a processor;
• and
• a storage device coupled to the processor, the storage device comprising:
• a group of memory cells each having a magnetoresistive element, the magnetoresistive elements of the memory cells in the group coupled in a voltage divider arrangement, the voltage divider arrangement providing a sense node;
• and
• a sense amplifier to receive a first signal from the sense node during a first sense phase of a read operation, and to receive a second signal from the sense node during a second sense phase of the read operation,
• the sense amplifier having an analog comparator to compare the first and second signals to determine a storage state of one of the memory cells in the group.

A method comprising:

• storing data in memory cells of a storage device, the memory cells each having a magnetoresistive element, wherein a group of the memory cells are arranged such that the magnetoresistive element of a selected one of the memory cells in the group is connected between a first voltage and a sense node, and the magnetoresistive elements of un-selected memory cells in the group are connected in parallel between the sense node and a second voltage;
• receiving plural signals from the sense node in respective plural sense phases of a read operation;
• and
• comparing the received plural signals, with an analog comparator, to determine a storage state of the selected one of the memory cells in the group.

A storage device comprising:

• memory cells each including a magnetic element, the memory cells including a first memory cell connected between a first voltage and a sense node, and at least second and third memory cells connected in parallel between the sense node and a reference voltage;
• and
• a sampling circuit coupled to the sense node, the sampling circuit configured to receive a first voltage sample corresponding to an original state of the first memory cell, and to store a second voltage sample corresponding to a known state of the first memory cell after the first memory cell has been written to the known state;
• and
• a differential amplifier to compare the first and second voltage samples in their analog forms.

A method comprising:

• storing data in memory cells of a storage device, the memory cells each having a magnetic element, wherein a group of the memory cells is arranged such that a first memory cell in the group is connected between a first voltage and a sense node, and plural other memory cells in the group are connected in parallel between the sense node and a second voltage;
• sampling an original state of the first memory cell through the sense node to produce a first voltage sample;
• writing a known state to the first memory cell;
• resampling the first memory cell after the writing to produce a second voltage sample;
• and
• comparing the first and second voltage samples in their analog form to determine the state of the first memory cell.