EP0447057A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Digital computer with non-hierarchical memory
Assignee: Hitachi Ltd
•
Filing: 1991-02-26
•
Granted: —
•
Expires: 2011-02-26
Abstract
Abstract A single storage device which is basically configured of semiconductor memories of large capacity, is employed as a main storage and an auxiliary storage for a digital processor such as personal computer. The storage device is brought into the shape of a card so as to be detachably connected to the personal computer or the like with ease.
Inventors
- 👤 Masamichi Ishihara
- 👤 Toshiyuki Sakuta
- 👤 Masanori Tazunoki
- 👤 Hisashi Nakamura
- 👤 Hiroyuki Uchiyama
- 👤 Jun Murata
- 👤 Shigetoshi Sakomura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 15:19
CPC Classifications
G; G06; G06F; G06F12/00; G11; G11C; G11C5/00; G11C5/02; G11C5/025; G11C5/14; G11C5/141
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
40 words
A digital processor comprising a central processing unit (CPU), and a storage device which includes semiconductor memories and which functions as a main storage and an auxiliary storage, said main storage and said auxiliary storage having a non-hierarchic storing architecture.
Claim 2
Dependent Claim
26 words
A digital processor as defined in Claim 1, wherein said storage device is in a shape in which it is detachably connected to said digital processor.
Claim 3
Dependent Claim
19 words
A digital processor as defined in Claim 2, wherein said storage device is in the shape of a card.
Claim 4
Dependent Claim
37 words
A digital processor as defined in Claim 3, wherein said storage device is exclusively used in correspondence with a processing content of said digital processor and is selectively connected to said digital processor for the processing content.
Claim 5
Dependent Claim
41 words
A digital processor as defined in Claim 4, wherein said each semiconductor memory is constructed of a dynamic RAM, a memory array portion of which is fed with an internal supply voltage having an absolute value substantially equal to 2.5 volts.
Claim 6
Dependent Claim
17 words
A digital processor as defined in Claim 4, wherein said digital processor is in a portable shape.
Claim 7
Dependent Claim
35 words
A memory card as defined in Claim 5, wherein an insulator film which corresponds to an information storing node of each of memory cells constituting said memory array portion is made of tantalum oxide (Ta₂O₅).
Claim 8
Dependent Claim
34 words
A memory card as defined in Claim 7, wherein said each memory cell is a member selected from the group consisting of a stacked capacitor type memory cell and a crown type memory cell.
Claim 9
Dependent Claim
28 words
A memory card as defined in Claim 8, comprising a voltage dropping circuit which forms said internal supply voltage on the basis of a predetermined external supply voltage.
Claim 10
Dependent Claim
36 words
A memory card as defined in Claim 9, comprising a secondary battery which feeds either of said external supply voltage and said internal supply voltage when said memory card is not connected to said digital processor.
Claim 11
Dependent Claim
22 words
A memory card as defined in Claim 10, comprising a solar battery which is connected substantially in parallel with said secondary battery.
Claim 12
Dependent Claim
38 words
A memory card as defined in Claim 11, wherein an absolute value of either of said external supply voltage and said internal supply voltage is set integral times as large as unit electromotive force of said secondary battery.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.