US4464735A
Expired / Lapsed
US
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Semiconductor memory
Assignee: Fujitsu Ltd
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Filing: 1981-12-11
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Granted: 1984-08-07
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Expires: 2001-12-11
Abstract
Abstract A semiconductor memory includes memory cells each respectively provided with a flip-flop circuit in which a pair of transistors is included, the flip-flop circuit being connected to a pair of bit lines and to a pair of word lines. The semiconductor memory further includes a pair of switching transistors connected to the pair of bit lines. One of the pair of switching transistors is turned ON while the other is turned OFF when they receive high and low potentials according to write data at the time of a write operation so as to flow write current from a memory cell to a voltage source via one of the pair of bit lines and one of the pair of switching transistors.
Inventors
- 👤 Kazuhiro Toyoda
- 👤 Yasuhisa Sugo
- 👤 Katuyuki Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:40
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/41; G11C11/413; G11C11/414; G11C11/416
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
184 words
A semiconductor memory having a write cycle and being operatively connected to receive write data, including: a memory cell having a pair of first transistors cross coupled to each other, each transistor having a first conductivity type, a base, a collector and an emitter; a pair of word lines respectively connected to said pair of first transistors; a pair of bit lines respectively connected to a corresponding one of the emitters of said pair of first transistors; a pair of second transistors, each of said pair of second transistors having a conductivity type different than said first conductivity type, having a base, having a collector, and having an emitter connected to a respective one of said pair of bit lines; and means for providing complementary signals responsive to said write data, said complementary signals being applied to respective ones of the bases of said pair of second transistors so that a write current flows from the memory cell to a voltage source means via one of said pair of bit lines and one of said pair of second transistors only during the write cycle.
Claim 2
Dependent Claim
184 words
A semiconductor memory having a write cycle and being operatively connected to receive write data, including: a memory cell having a pair of first transistors cross coupled to each other, each transistor having a first conductivity type, a base, a collector and an emitter; a pair of word lines respectively connected to said pair of first transistors; a pair of bit lines respectively connected to a corresponding one of the emitters of said pair of first transistors; a pair of second transistors, each of said pair of second transistors having a conductivity type different than said first conductivity type, having a base, having a collector, and having an emitter connected to a respective one of said pair of bit lines; and means for providing complementary signals responsive to said write data, said complementary signals being applied to respective ones of the bases of said pair of second transistors so that a write current flows from the memory cell to a voltage source means via one of said pair of bit lines and one of said pair of second transistors only during the write cycle.
Claim 3
Dependent Claim
17 words
A semiconductor memory according to claim 1, wherein each of said second transistors is a PNP transistor.
Claim 4
Dependent Claim
66 words
A semiconductor memory according to claim 2, wherein said semiconductor memory comprises a further pair of transistors, each of said further pair of transistors having collectors connected to the base of said NPN transistor and to said voltage source means via a resistor, having emitters connected to each other, and having bases, connected to said means for supplying complementary signals, for respectively receiving said complementary signals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-07 | 1988-02-06 | 1988-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-07 | 1992-02-06 | 1992-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-07 | 1996-02-06 | 1996-08-07 | $7700.00 | Window Closed / Lapsed |