Semiconductor memory device realizing high-speed access
In data read, a single read global bit line is shared with a plurality of local bit lines.
1. A semiconductor memory device comprising a plurality of integrated hierarchical arrays each having: a plurality of hierarchical arrays each including a plurality of memory cells connected to a first bit line and a second bit line and a read/write circuit connected to the first bit line, a write signal line and a hierarchical precharge control signal line; and an integrated circuit connected to the plurality of hierarchical arrays and a main read signal line, wherein the plurality of second bit lines, the plurality of write signal lines and the main read signal line are shared with the plurality of integrated hierarchical arrays.
2. The semiconductor memory device according to claim 1 , wherein the read/write circuit includes: a hierarchical precharge control circuit having a hierarchical precharge transistor connected to the first bit line and the hierarchical precharge control signal line and controlling the hierarchical precharge transistor through the hierarchical precharge control signal line; and a second precharge circuit having a plurality of second precharge transistors connected to the plurality of second bit lines and the main read signal line, respectively.
3. The semiconductor memory device according to claim 2 , wherein the hierarchical precharge transistor is smaller in size than the second precharge transistor.
4. The semiconductor memory device according to claim 2 , wherein the hierarchical precharge control circuit is connected to a column decode signal line, and is provided in a row decoder.
5. The semiconductor memory device according to claim 1 , wherein the integrated circuit is configured by using a logic circuit.
6. The semiconductor memory device according to claim 2 , wherein the integrated circuit includes an integrated precharge transistor precharging data outputted from the hierarchical array, and the hierarchical precharge control circuit includes an integrated precharge control circuit controlling the integrated precharge transistor through an integrated precharge control signal line.
7. The semiconductor memory device according to claim 2 , wherein the read/write circuit includes a P-channel transistor having a gate connected to the first bit line, an N-channel transistor having a gate connected to the write signal line, and a P-channel transistor having a gate connected to the hierarchical precharge control signal line from the hierarchical precharge control circuit.
8. The semiconductor memory device according to claim 6 , wherein the integrated precharge control circuit stops the plurality of integrated precharge transistors concurrently.
9. The semiconductor memory device according to claim 2 , further comprising a read data control circuit connected to the main read signal line.
10. The semiconductor memory device according to claim 2 , wherein the integrated circuit includes a first switch inhibiting data transfer in data write.
11. The semiconductor memory device according to claim 2 , wherein the read/write circuit includes a second switch inhibiting data transfer in data write.
12. The semiconductor memory device according to claim 2 , wherein the integrated precharge control circuit of the hierarchical precharge control circuit is connected to a word line activation signal line.