Static random access memory having a memory cell operating voltage larger than an operating voltage of a peripheral circuit
View Patent ↗A static memory cell, composed of cross-coupled MOS transistors having a relatively high threshold voltage, is equipped with MOS transistors for controlling the power supply line voltage of the memory cell. To permit the voltage difference between two data storage nodes in the inactivated memory cell to exceed the voltage difference between the two nodes when write data is applied from a data line pair DL and /DL to the two nodes in the activated memory cell, the power supply line voltage control transistors are turned on to apply a high voltage VCH to the power supply lines after the word line voltage is turned off. The data holding voltage in the memory cell can be activated to a high voltage independent of the data line voltage, and the data holding voltage can be dynamically set so that read and write operations can be performed at high speed with low power consumption.
1. A semiconductor integrated circuit device for a static random access memory comprising:
a plurality of static random access memory cells each comprised of two load MOS transistors, two driver MOS transistors, and two transfer MOS transistors;
a plurality of word lines coupled to the gates of said transfer MOS transistors;
a plurality of data lines coupled to said plurality of static random access memory cells; and
a peripheral circuit comprising MOS transistors and controlling said plurality of static random access memory cells,
wherein said word lines which are not selected are set to a negative voltage; and
wherein the operating voltage supplied to said MOS transistors of said static random access memory cells is larger than the operating voltage supplied to the MOS transistors of said peripheral circuit.
2. The semiconductor integrated circuit device according to claim 1 ,
wherein a first voltage and a second voltage are supplied to each of said static random access memory cells; and
wherein said word lines which are not selected are set to a voltage lower than said second voltage and lower than said first voltage.
3. The semiconductor Integrated circuit device according to claim 2 ,
wherein the threshold voltage of said transfer MOS transistors is smaller than the threshold voltage of said driver MOS transistors.
4. A semiconductor integrated circuit device for a static random access memory comprising:
a plurality of static random access memory cells each comprised of two load MOS transistors, two driver MOS transistors, and two transfer MOS transistors;
a plurality of word lines coupled to the gates of said transfer MOS transistors;
a plurality of data lines coupled to said plurality of static random access memory cells; and
a peripheral circuit comprising MOS transistors and controlling said plurality of static random access memory cells,
wherein said word lines which are not selected are set to a negative voltage;
wherein the operating voltage supplied to the MOS transistors of said static random access memory cells is larger than the operating voltage supplied to the MOS transistors of said peripheral circuit; and
wherein the voltage supplied to the sources of said driver MOS transistors is higher than said negative voltage.
5. The semiconductor integrated circuit device according to claim 4 ,
wherein the threshold voltage of said transfer MOS transistors is smaller than the threshold voltage of said driver MOS transistors.
6. The semiconductor integrated circuit device according to claim 4 ,
wherein said semiconductor integrated circuit device is formed on an N type substrate having a P type well, and
wherein said two load MOS transistors of one of said static random access memory cells are embedded in said P type well.