Folded read-only memory

Details Folded read-only memory Folded read-only memory

1997-10-29

1998-10-20

Nelms, David C.

Static information storage and retrieval

Read only systems

Semiconductive

365 63, 36518513, 36518516, G11C 1700

Patent

active

058256830

ABSTRACT:
In a "flat cell" read-only memory with a matrix of memory cells, each memory cell is a MOSFET of either a low threshold voltage, which can be turned on when accessed, or a high threshold voltage which cannot be turned on when accessed. Each memory cell is connected between two adjacent columns of local bit lines. These local bit lines are alternately connected to a upper bank selection switch which is connected to a main bit line, and a lower bank selection switch, which is connected to a main virtual ground line. Since these local bit lines are fabricated with diffusion layers which are resistive, the path length, hence the resistance, to access any memory cell in the matrix from the main bit line to the main virtual ground is made the same by this alternate, interdigital local bit line layout. Thus, the access time is made uniform.
The layouts of two adjacent banks are mirrored, so that the bank selection switches of two adjacent banks can share a common selection line.

REFERENCES:
patent: 5117389 (1992-05-01), Yiu
patent: 5268861 (1993-12-01), Hotta
patent: 5295092 (1994-03-01), Hotta
patent: 5341337 (1994-08-01), Hotta
patent: 5392233 (1995-02-01), Iwase
patent: 5600586 (1997-02-01), Lee
patent: 5625586 (1997-04-01), Yamasaki et al.
patent: 5721698 (1998-02-01), Lee et al.

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