ROM semiconductor integrated circuit device having a plurality of common source lines
In a semiconductor integrated circuit device having a volatile memory high-speed operation is enabled and the density of the memory can be enhanced. The volatile memory includes a word line, a complementary bit line having bit lines, a plurality of common source lines, and a memory cell that is coupled with the word line and the complementary bit lines. The memory cell includes transistors. The gate electrodes of the transistors are coupled with the word line, and the drain electrode of one of the transistors is coupled with one of the bit lines. The drain electrode of the other transistor is coupled with the other bit line. The respective source electrodes of the transistors are coupled with any one of the common source lines, or brought in a floating state, thereby storing storage information in the memory cell.
1. A semiconductor integrated circuit device having a nonvolatile memory cell, comprising:
a word line;
complementary bit lines including first and second bit lines;
two or more N common source lines; and
a memory cell that is coupled with the word line and the complementary bit lines;
wherein the nonvolatile memory cell includes first and second transistors,
wherein the gates of the first and second transistors are coupled with the word line,
wherein the source or drain of the first transistor is coupled with the first bit line;
wherein the source or drain of the second transistor is coupled with the second bit line;
wherein the source or the drain which are different from the source or the drain coupled with the bit lines of the first and second transistors is coupled with any one of the first to N common source lines, or brought in a floating state to store storage information in the nonvolatile memory cell.
2. The semiconductor integrated circuit device according to claim 1 ,
wherein the first common source line is transited to a first potential, and any one of the N common source lines is transited to the first potential during the read operation of the memory cell.
3. The semiconductor integrated circuit device according to claim 1 ,
wherein the memory cell stores data of N bits therein.
4. The semiconductor integrated circuit device according to claim 1 ,
wherein the write of data in the memory cell is conducted by coupling an M-th metal wiring layer that forms the first common source line and the N common source lines with an (M−1)-th metal wiring layer that is coupled with the drains or sources of the first and second transistors.
5. A semiconductor integrated circuit device having a nonvolatile memory, the nonvolatile memory comprising:
a word line;
complementary bit lines including first and second bit lines;
first, second, and third common source lines;
a memory cell that is coupled with the word line and the complementary bit line; and
a differential sense amplifier that is coupled with the complementary bit line,
wherein the memory cell includes first and second transistors,
wherein the gate electrodes of the first and second transistors are coupled with the word line,
wherein the drain electrode of the first transistor is coupled with the first bit line,
wherein the drain electrode of the second transistor is coupled with the second bit line, and
wherein each source electrode of the first and second transistors is coupled with any one of the first, second, and third common source lines, or brought in a floating state, to store memory information in the memory cell.
6. The semiconductor integrated circuit device according to claim 5 ,
wherein the first common source line is transited to a first potential, and any one of the second and third common source lines is transited to the first potential during the read operation of the memory cell.
7. The semiconductor integrated circuit device according to claim 5 ,
wherein the nonvolatile memory stores two data within the one memory cell.
8. The semiconductor integrated circuit device according to claim 5 ,
wherein the write of data in the memory cell is conducted by coupling an M-th metal wiring layer that forms the first common source line, and the second and third common source lines with an (M−1)-th metal wiring layer that is coupled with the drains of the first and second transistors.
9. A semiconductor integrated circuit device having a nonvolatile memory, the nonvolatile memory comprising:
a word line;
complementary bit lines including first and second bit lines;
first to fifth common source lines;
a memory cell that is coupled with the word line and the complementary bit lines; and
a differential sense amplifier that is coupled with the complementary bit lines,
wherein the memory cell includes a first and second transistors,
wherein the gate electrodes of the first and second transistors are coupled with the word line,
wherein the drain electrode of the first transistor is coupled with the first bit line,
wherein the drain electrode of the second transistor is coupled with the second bit line, and
wherein each source electrode of the first and second transistors is coupled with any one or more of the first to fifth common source lines or brought in a floating state, to store memory information in the memory cell.
10. The semiconductor integrated circuit device according to claim 9 ,
wherein the first common source line is transited to a first potential, and any one of the second to fifth common source lines is transited to the first potential during the read operation of the nonvolatile memory.
11. The semiconductor integrated circuit device according to claim 9 ,
wherein the nonvolatile memory stores four data within the one memory cell.
12. The semiconductor integrated circuit device according to claim 9 ,
wherein the write of data in the memory cell is conducted by coupling an M-th metal wiring layer that forms the first to fifth common source lines with an (M−1)-th metal wiring layer that is coupled with the drains of the first and second transistors.