Method and apparatus for programming a spin-transfer torque magnetic random access memory (STTMRAM) array
View Patent ↗A spin-transfer torque memory random access memory (STTMRAM) cell is disclosed comprising a selected magnetic tunnel junction (MTJ) identified to be programmed; a first transistor having a first port, a second port and a gate, the first port of the first transistor coupled to the selected MTJ; a first neighboring MTJ coupled to the selected MTJ through the second port of the first transistor; a second transistor having a first port, a second port, and a gate, the first port of the second transistor coupled to the selected MTJ; a second neighboring MTJ coupled to the selected MTJ through the second port of the second transistor; a first bit/source line coupled to the second end of the selected MTJ; and a second bit/source line coupled to the second end of the first neighboring MTJ and the second end of the second neighboring MTJ.
1. A spin-transfer torque magnetic random access memory (STTMRAM) array comprising:
a selected magnetic tunnel junction (MTJ) to be programmed by switching the state thereof upon application of a switching current, the selected MTJ coupled to a first transistor and a second transistor;
a first neighboring MTJ coupled to the first transistor; and
a second neighboring MTJ coupled to the second transistor,
wherein during programming of the selected MTJ, a first current flows through the first transistor and a second current flows through the second transistor and the first current is equal to or less than twenty five percent (25%) of the second current.
2. The STTMRAM array of claim 1 , wherein the second current is the maximum current that the second transistor can supply.
3. The STTMRAM array of claim 1 , wherein the first current is between ten percent (10%) to twenty percent (20%) of the second current.
4. The STTMRAM array of claim 1 , wherein the first current is equal to or less than the current flowing through the first neighboring MTJ during a read operation of the first neighboring MTJ.
5. The STTMRAM array of claim 4 , wherein the first neighboring MTJ is programmed prior to programming of the selected MTJ.
6. The STTMRAM array of claim 1 , wherein the first neighboring MTJ does not store data and is a sacrificial MTJ.
7. The STTMRAM array of claim 1 , wherein the second neighboring MTJ is not programmed prior to programming of the selected MTJ.
8. The STTMRAM array of claim 7 , wherein the second neighboring MTJ does not store data and is a sacrificial MTJ.
9. A spin-transfer torque magnetic random access memory (STTMRAM) array comprising:
a selected magnetic tunnel junction (MTJ) to be programmed by switching the state thereof upon application of a switching current, the selected MTJ having a first end and a second end;
a first transistor having a first port, a second port and a gate, the first port of the first transistor coupled to the selected MTJ at the first end of the selected MTJ;
a first neighboring MTJ having a first end and a second end, the first end of the first neighboring MTJ coupled to the second port of the first transistor;
a second transistor having a first port, a second port, and a gate, the first port of the second transistor coupled to the selected MTJ at the first end of the selected MTJ;
a second neighboring MTJ having a first end and a second end, the first end of the second neighboring MTJ coupled to the second port of the second transistor,
wherein during programming of the selected MTJ, a first current flows through the first transistor and a second current flows through the second transistor and the first current is equal to or less than twenty five percent (25%) of the second current.
10. The STTMRAM array of claim 9 , wherein the second current is the maximum current that the second transistor can supply.
11. The STTMRAM array of claim 9 , wherein the first current is between ten percent (10%) to twenty percent (20%) of the second current.
12. The STTMRAM array of claim 9 , wherein the first current is equal to or less than the current flowing through the first neighboring MTJ during a read operation of the first neighboring MTJ.
13. The STTMRAM array of claim 12 , wherein the first neighboring MTJ is programmed prior to programming of the selected MTJ.
14. The STTMRAM array of claim 9 , wherein the first neighboring MTJ does not store data and is a sacrificial MTJ.
15. The STTMRAM array of claim 9 , wherein the second neighboring MTJ is not programmed prior to programming of the selected MTJ.
16. The STTMRAM array of claim 15 , wherein the second neighboring MTJ does not store data and is a sacrificial MTJ.