Apparatuses and methods including memory and operation of same
View Patent ↗Disclosed herein is a memory cell. The memory cell may act both as a combined selector device and memory element. The memory cell may be programmed by applying write pulses having different polarities. Different polarities of the write pulses may program different logic states into the memory cell. The memory cell may be read by read pulses all having the same polarity. The logic state of the memory cell may be detected by observing different threshold voltages when the read pulses are applied. The different threshold voltages may be responsive to the different polarities of the write pulses.
1. An apparatus, comprising:
a memory cell;
a first memory access line coupled to the memory cell; and
a second memory access line coupled to the memory cell,
wherein the first and second memory access lines are configured to provide a write pulse having a first or second polarity across the memory cell,
wherein, during a read operation, the memory cell is determined to be in a first or second logic state based on a current through the memory cell responsive to a read pulse having the first polarity applied to the memory cell,
wherein the current is provided through the memory cell responsive to one of first and second threshold voltages exhibited by the memory cell during the read operation on the memory cell, and
wherein, during the read operation, the memory cell is determined to be in the first logic state if the current through the memory cell responsive to the first threshold voltage of the memory cell is equal to or above a threshold current, or determined to be in the second logic state if the current through the memory cell responsive to the second threshold voltage of the memory cell is below the threshold current.
2. The apparatus of claim 1 , wherein the first and second threshold voltages are representative of the first and second logic states, respectively.
3. The apparatus of claim 1 , wherein the first threshold voltage representative of the first logic state is exhibited by the memory cell responsive to the read operation when the write pulse having the first polarity was provided to the memory cell.
4. The apparatus of claim 1 , wherein the second threshold voltage representative of the second logic state is exhibited by the memory cell responsive to the read operation when the write pulse having the second polarity was provided to the memory cell.
5. The apparatus of claim 1 , further comprising a sense amplifier coupled to the first memory access line or the second memory access line,
wherein the sense amplifier is configured to sense the current through the memory cell responsive to the read pulse.
6. The apparatus of claim 1 , wherein the read pulse has a magnitude between a magnitude of the first threshold voltage of the memory cell and a magnitude of the second threshold voltage of the memory cell.
7. The apparatus of claim 1 , wherein the first and second memory access lines are configured to provide the write pulse during a write operation.
8. The apparatus of claim 1 , wherein the write pulse having the first polarity is provided across the memory cell to write the first logic state to the memory cell and the write pulse having the second polarity is provided across the memory cell to write the second logic state to the memory cell.