Field
This disclosure relates generally to integrated circuits, and more particularly, to sensing and reference voltage schemes for one transistor one resistor (1T1R) random access memory (RAM) cells.
Related Art
As voltages used in memory devices for modern consumer electronics are ever decreasing, traditional techniques for sensing voltage or current to read the state of memory cells become inadequate. In particular, for memory cells that use only 1 transistor and 1 resistor (1T1R), the difference between voltage or current being sensed during a read operation may be within the same order of magnitude as any bias or offset that may be present due to offset error in sense amplifiers of the memory device. Further, it is desirable to keep voltages used during read operations below a level that might change the state of a memory cell. Due to small differences in currents and low voltages during read operations, it is challenging to sense the state of memory cells quickly in a power efficient manner. Due to low voltage, current sensing may be used, but errors in current mirrors can give inaccurate results.
Accordingly there is a need to provide further improvement in sensing 1T1R RAM cells.