US5465229A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single in-line memory module
Assignee: Sun Microsystems Inc
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Filing: 1994-11-28
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Granted: 1995-11-07
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Expires: 2014-11-28
Abstract
Abstract A full width single in-line memory module (SIMM) for dynamic random access memory (DRAM) memory expansions is disclosed. A printed circuit board having a multiplicity of DRAM memory elements mounted thereto is arranged in a data path having a width of 144 bits. The SIMM of the present invention further includes on-board drivers to buffer and drive signals in close proximity to the memory elements. In addition, electrically conductive traces are routed on the circuit board in such a manner to reduce loading and trace capacitance to minimize signal skew to the distributed memory elements. The SIMM further includes a high pin density dual readout connector structure receiving electrical traces from both sides of the circuit board for enhanced functionality. The SIMM is installed in complementary sockets one SIMM, at a time to provide memory expansion in full width increments. Finally, symmetrical power and ground routings to the connector structure insure that the SIMM cannot be inserted incorrectly, wherein physically reversing the SIMM in the connector slot will not reverse power the SIMM.
Inventors
- 👤 Andreas Bechtolsheim
- 👤 Edward Frank
- 👤 James Testa
- 👤 Shawn Storm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:24
CPC Classifications
G; G11; G11C; G11C5/00; G11C5/02; G11C5/04; H; H05; H05K; H05K1/00; H05K1/02; H05K1/11; H05K1/117; H05K1/14; H05K1/141; H05K1/18; H05K1/181; H05K2201/00; H05K2201/09; H05K2201/09209; H05K2201/095; H05K2201/09645; H05K2201/10; H05K2201/10613; H05K2201/10621; H05K2201/10689; H05K2203/00; H05K2203/15; H05K2203/1572; H05K3/00; H05K3/40; H05K3/403; Y; Y10; Y10S; Y10S439/00; Y10S439/951
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
116 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector; a first set of memory elements arranged on said printed circuit board, said set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 2
Dependent Claim
116 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector; a first set of memory elements arranged on said printed circuit board, said set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 3
Dependent Claim
38 words
A single in-line memory module as claimed in claim 1 wherein said electrical connector comprises a full width data path such that one of said single in-line memory modules can increase a main memory in said computer system.
Claim 4
Dependent Claim
20 words
A single in-line memory module as claimed in claim 2 wherein said full width data path comprises 144 data lines.
Claim 5
Dependent Claim
43 words
A single in-line memory module as claimed in claim 1 wherein said electrical connector has symmetrical power and ground contacts such that said single in-line memory module is not damaged if said single in-line memory module is inserted into said computer system backwards.
Claim 6
Dependent Claim
100 words
A single in-line memory module as claimed in claim 1 wherein said single in-line memory module further comprises the elements of: a second set of memory elements arranged on said printed circuit board, said first and second set of memory elements having a total of at least n data lines; and a driver circuit mounted substantially centered on said first side of said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements and said second set of memory elements.
Claim 7
Dependent Claim
94 words
A single in-line memory module as claimed in claim 5 wherein: said first set of memory elements is arranged on the first side of said printed circuit board and comprises a first subset arranged to the left of said driver circuit and a second subset arranged to the right of said driver circuit; and said second set of memory elements is arranged on the second side of said printed circuit board and comprises a third subset being mirror image of said first subset and a fourth subset being mirror image of said second subset.
Claim 8
Dependent Claim
61 words
A single in-line memory module as claimed in claim 6 wherein said first, second, third, and fourth subsets of memory elements each comprise nine memory elements arranged in a three by three matrix and said driver circuit transmits said control signals directly to a center memory element in said first and second memory element subsets such that signal skew is minimized.
Claim 9
Dependent Claim
31 words
A single in-line memory module as claimed in claim 7 wherein said control signals comprise column address strobe (CAS), row address strobe (RAS), write enable (WE), and output enable (OE) signals.
Claim 10
Dependent Claim
18 words
A single in-line memory module as claimed in claim 8 wherein said driver circuit further drives address lines.
Claim 11
Dependent Claim
44 words
(Added) A single in-line memory module as claimed in claim 5 wherein said electrical connector has symmetrical power and ground contacts such that said single in-line memory module is not damaged if said single in-line memory module is inserted into said computer system backwards.
Claim 12
Dependent Claim
40 words
A single in-line memory module as claimed in claim 5 wherein said single in-line memory module provides data in a first data path at least as wide a second data path used a central processing unit in said computer system.
Claim 13
Dependent Claim
151 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector, said electrical connector comprising a first set of electrical contacts on said first side of said printed circuit board and a second set of electrical contacts on said second side of said printed circuit board; a first set of memory elements arranged on said printed circuit board, said set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 14
Dependent Claim
151 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector, said electrical connector comprising a first set of electrical contacts on said first side of said printed circuit board and a second set of electrical contacts on said second side of said printed circuit board; a first set of memory elements arranged on said printed circuit board, said set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 15
Dependent Claim
28 words
The single in-line memory module for memory expansion of claim 12 wherein said first set of electrical contacts and said second set of electrical contacts are electrically distinct.
Claim 16
Dependent Claim
200 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector, said electrical connector comprising a first set of electrical contacts on said first side of said printed circuit board and a second set of electrical contacts on said second side of said printed circuit board; a first set of memory elements arranged on said first side of said printed circuit board, said first set of memory elements coupled to first set of electrical contacts; a second set of memory elements arranged on said second side of said printed circuit board, said second set of memory elements coupled to second set of electrical contacts, said first and second set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 17
Dependent Claim
200 words
A single in-line memory module for memory expansion in a computer system having a memory bus with n data lines, said single in-line memory module comprising the elements of: a printed circuit board, said printed circuit board having a first side and a second side, said printed circuit board having an electrical connector, said electrical connector comprising a first set of electrical contacts on said first side of said printed circuit board and a second set of electrical contacts on said second side of said printed circuit board; a first set of memory elements arranged on said first side of said printed circuit board, said first set of memory elements coupled to first set of electrical contacts; a second set of memory elements arranged on said second side of said printed circuit board, said second set of memory elements coupled to second set of electrical contacts, said first and second set of memory elements having a total of at least n data lines; and a driver circuit mounted on said printed circuit board, said driver circuit coupled to a set control signals in said electrical connector, said driver circuit transmitting said controls signals to said first set of memory elements.
Claim 18
Dependent Claim
28 words
The single in-line memory module for memory expansion of claim 14 wherein said first set of electrical contacts and said second set of electrical contacts are electrically distinct.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-11-06 | 1999-05-08 | 1999-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-11-06 | 2003-05-08 | 2003-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-11-06 | 2007-05-08 | 2007-11-07 | $7700.00 | Window Closed / Lapsed |