HIGH SPEED DIFFERENTIAL SENSE AMPLIFIER FOR USE WITH SINGLE TRANSISTOR MEMORY CELLS
 Inventors: Alaaeldin A. M. Amin, Dhahran, Saudi Arabia; Bernard Emoto, Midvale, Utah
 Assignee: National Semiconductor Corp., Santa Clara, Calif.
 Appl. No.: 698,257
 Filed: May 6,1991
Related U.S. Application Data
 Continuation of Ser. No. 276,363, Nov. 23, 1988, abandoned.
 Int. C1.5 G11C 16/06
 U.S. CI 365/203; 365/202;
365/185; 365/208; 365/210
 Field of Search 365/104, 185, 189.09,
365/202, 203, 205, 207, 208, 210
 References Cited
U.S. PATENT DOCUMENTS
4,475,178 10/1984 Kinoshita 365/203
4,654,831 3/1987 Venkatesh 365/207
4,725,984 2/1988 Ip et al 365/185
4,802,138 1/1989 Shimamune 365/208
4,829,479 5/1989 Mitsumoto et al 365/189.09
4,903,237 2/1990 Rao 365/185
OTHER PUBLICATIONS "The Technology of a 1MBIT CMOS EPROM", by G.
Nelmes, New Electronics, vol. 18, No. 22, Nov. 1985, pp. 70-74.
"A 1MB CMOS EPROM with Enhanced Verification", by D. Novosel et al., 1988 IEEE Solid-State Circuits Conference, Digest of Technical Papers, 17th-19th Feb. 1988, pp. 124-125, 325.
Primary Examiner—Glenn Gossage
Attorney, Agent, or Firm—Steven F. Caserza; Irv
A memory circuit incorporates a differential sense amplifier to be utilized in conjunction with a memory array comprised of a plurality of memory cells each containing a single transistor. A high slew rate differential input signal is applied to the sense amplifier based upon the binary data stored in an addressed memory cell. This is accomplished by pre-charging the selected bit line and a reference bit line, and then selecting the word line of the memory cell to be read, while causing the reference memory cell to conduct. The differential voltage between the selected bit line and the reference bit line is then sensed to determine the state of the data stored in the selected memory cell. The ratio of currents through the selected bit line and the reference bit line is selected to be other than one, in order to achieve a rapid differential voltage swing, and rapid reading of the data stored within the selected memory cell.
8 Claims, 3 Drawing Sheets