Circuit to improve SRAM stability
Approaches for stability of cells in a Static Random Access Memory (SRAM) array are provided. A circuit includes a precharging circuit configured to precharge bitlines of a Static Random Access Memory (SRAM) array to a first voltage potential for a non-read operation and to a second voltage potential for a read operation. The first voltage potential is different than the second voltage potential.
1. A method, comprising:
precharging bitline pairs of a Static Random Access Memory (SRAM) array to a first voltage potential for a non-read operation;
precharging only a single one of the bitline pairs to a second voltage potential for a read operation, wherein the first voltage potential is less than the second voltage potential, and wherein the single one of the bitline pairs corresponds to a column that contains a selected cell of the read operation; and
precharging all other ones of the bitlines pairs, exclusive of the single one of the bitline pairs, to the first voltage potential for the read operation.
2. The method of claim 1 , wherein the bitline pairs are precharged by a charging circuit comprising:
a header switch connected between a high voltage supply level and a precharge line; and
a voltage drop device connected between the high voltage supply level and the precharge line.
3. The method of claim 2 , wherein:
the header switch is selectively turned on and off by a control signal applied to a gate of the header switch;
the precharge line is configured to be charged to the first voltage potential when the header switch is off; and
the precharge line is configured to be charged to the second voltage potential when the header switch is on.