US5808952A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adaptive auto refresh
Assignee: Promos Technologies Inc
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Filing: 1996-10-28
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Granted: 1998-09-15
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Expires: 2016-10-28
Abstract
Abstract A system and method for automatically refreshing a dynamic random access memory is disclosed. The system comprises a timer, a trigger, and refresh generation means coupled to the timer and the trigger. The timer provides a first refresh rate. The first refresh rate is a required number of refreshes for a particular interval of time. The trigger provides a trigger signal. The trigger signal is a periodic signal. The refresh generation provide a plurality of refreshes at a second refresh rate in response to the trigger signal. The system functions such that the second refresh rate adapts to the first refresh rate.
Inventors
- 👤 Michael G. Fung
- 👤 Fukuji D. Sugie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:24
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/401; G11C11/406
Claims Analysis
Total Claims: 52
Claim 1
Independent Claim
95 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; a trigger for providing a trigger signal the trigger signal being a periodic signal having a trigger signal rate; and refresh generation means coupled to the trigger and the timer for providing a plurality of refreshes at a second refresh rate; such that the second refresh rate adapts to the first refresh rate in response to the trigger signal rate.
Claim 2
Independent Claim
95 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; a trigger for providing a trigger signal the trigger signal being a periodic signal having a trigger signal rate; and refresh generation means coupled to the trigger and the timer for providing a plurality of refreshes at a second refresh rate; such that the second refresh rate adapts to the first refresh rate in response to the trigger signal rate.
Claim 3
Dependent Claim
34 words
The system of claim 1 wherein the refresh generation means further generate refreshes at a third refresh rate when the trigger is disabled, the third refresh rate being at least the first refresh rate.
Claim 4
Dependent Claim
11 words
The system of claim 2 wherein the trigger signal is variable.
Claim 5
Dependent Claim
30 words
The system of claim 3 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each occurrence of the trigger signal.
Claim 6
Dependent Claim
51 words
The system of claim 4 wherein the refresh generation means further comprises: a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; and a controller coupled to the counter for providing a plurality of refreshes at the second refresh rate.
Claim 7
Dependent Claim
35 words
The system of claim 5 wherein the refresh generation means further comprises a state machine coupled to the trigger and the counter, for changing a state of the counter in response to the trigger signal.
Claim 8
Dependent Claim
34 words
The system of claim 6 wherein the timer further comprises: a clock for generating a first rate; and a prescalar coupled to the clock, for scaling the first rate to the first refresh rate.
Claim 9
Dependent Claim
19 words
The system of claim 7 wherein an overflow signal from the counter is generated when the trigger is disabled.
Claim 10
Independent Claim
110 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; a trigger coupled to the counter for providing a trigger signal, the trigger signal being a periodic signal; and a controller coupled to the counter for providing a plurality of refreshes at a second refresh rate in response to the trigger signal such that the second refresh rate adapts to the first refresh rate.
Claim 11
Independent Claim
110 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; a trigger coupled to the counter for providing a trigger signal, the trigger signal being a periodic signal; and a controller coupled to the counter for providing a plurality of refreshes at a second refresh rate in response to the trigger signal such that the second refresh rate adapts to the first refresh rate.
Claim 12
Dependent Claim
32 words
The system of claim 9 wherein the controller further generates refreshes when the trigger is disabled at a third refresh rate, the third refresh rate being at least the first refresh rate.
Claim 13
Dependent Claim
19 words
The system of claim 10 wherein an overflow signal from the counter is generated when the trigger is disabled.
Claim 14
Dependent Claim
11 words
The system of claim 11 wherein the trigger signal is variable.
Claim 15
Dependent Claim
30 words
The system of claim 12 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each occurrence of the trigger signal.
Claim 16
Dependent Claim
32 words
The system of claim 13 wherein the counter further comprises a state machine, for causing refreshes to be performed to cause the counter to count down in response to the trigger signal.
Claim 17
Dependent Claim
34 words
The system of claim 14 wherein the timer further comprises: a clock for generating a first rate; and a prescalar coupled to the clock for scaling the first rate to the first refresh rate.
Claim 18
Independent Claim
102 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; counting means coupled to the timer for counting the required number of refreshes; a trigger coupled to the counter for providing a trigger signal the trigger signal being a periodic signal; and a controller coupled to the counter for providing a plurality of refreshes at a second refresh rate in response to the trigger signal, such that the second refresh rate adapts to the first refresh rate.
Claim 19
Independent Claim
102 words
A system for automatically refreshing a dynamic random access memory comprising: a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; counting means coupled to the timer for counting the required number of refreshes; a trigger coupled to the counter for providing a trigger signal the trigger signal being a periodic signal; and a controller coupled to the counter for providing a plurality of refreshes at a second refresh rate in response to the trigger signal, such that the second refresh rate adapts to the first refresh rate.
Claim 20
Dependent Claim
32 words
The system of claim 16 wherein the controller further generates refreshes at a third refresh rate when the trigger is disabled, the third refresh rate being at least the first refresh rate.
Claim 21
Dependent Claim
27 words
The system of claim 17 wherein when the trigger is disabled an overflow signal is generated that indicates that the counting means has reached a maximum count.
Claim 22
Dependent Claim
11 words
The system of claim 18 wherein the trigger signal is variable.
Claim 23
Dependent Claim
17 words
The system of claim 19 wherein the counting means further comprises a counter coupled to the timer.
Claim 24
Dependent Claim
43 words
The system of claim 20 wherein the counting means further comprises a state machine coupled to the counter and the trigger, the state machine for causing refreshes to be performed to cause the counter to count down in response to the trigger signal.
Claim 25
Dependent Claim
34 words
The system of claim 21 wherein the timer further comprises a clock for generating a first rate; and a prescalar coupled to the clock for scaling the first rate to the first refresh rate.
Claim 26
Dependent Claim
30 words
The system of claim 22 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each occurrence of the trigger signal.
Claim 27
Independent Claim
112 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer, the timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing a trigger, the trigger for providing a trigger signal, the trigger signal being a periodic signal having a trigger signal rate; and c) providing refresh generation means coupled to the trigger and the timer, the refresh generation means for providing a plurality of refreshes at a second refresh rate, such that the second refresh rate adapts to the first refresh rate in response to the trigger signal rate.
Claim 28
Independent Claim
112 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer, the timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing a trigger, the trigger for providing a trigger signal, the trigger signal being a periodic signal having a trigger signal rate; and c) providing refresh generation means coupled to the trigger and the timer, the refresh generation means for providing a plurality of refreshes at a second refresh rate, such that the second refresh rate adapts to the first refresh rate in response to the trigger signal rate.
Claim 29
Dependent Claim
48 words
The method of claim 24 wherein the refresh generation means providing step (c) further comprises the step of: c1) providing refresh generation means capable of generating refreshes at a third refresh rate when the trigger is disabled, the third refresh rate being at least the first refresh rate.
Claim 30
Dependent Claim
11 words
The method of claim 25 wherein the trigger signal is variable.
Claim 31
Dependent Claim
30 words
The method of claim 26 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each cycle of the trigger signal.
Claim 32
Dependent Claim
63 words
The method of claim 27 wherein the refresh generation means providing step (c) further comprises the steps of: c2) providing a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; and c3) providing a controller coupled to the counter, the controller for providing a plurality of refreshes at the second refresh rate.
Claim 33
Dependent Claim
48 words
The method of claim 28 wherein the refresh generation means providing step (c) further comprises the step of: c4) providing a state machine coupled to the trigger and the counter, the state machine for causing the counter to count up or down in response to the trigger signal.
Claim 34
Dependent Claim
45 words
The method of claim 29 wherein timer providing step (a) further comprises the steps of: a1) providing a clock for generating a first rate; and a2) providing a prescalar coupled to the clock, the prescalar for scaling the first rate to the first refresh rate.
Claim 35
Dependent Claim
20 words
The method of claim 30 wherein when an overflow signal from the counter is generated when the trigger is disabled.
Claim 36
Independent Claim
118 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; c) providing a trigger coupled to the counter, the trigger for providing a trigger signal; and d) providing a controller coupled to the counter, the controller for providing a plurality of refreshes at a second refresh rate in response to the trigger signal, such that the second refresh rate adapts to the first refresh rate.
Claim 37
Independent Claim
118 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing a counter coupled to the timer for counting the required number of refreshes, the counter counting at the first refresh rate; c) providing a trigger coupled to the counter, the trigger for providing a trigger signal; and d) providing a controller coupled to the counter, the controller for providing a plurality of refreshes at a second refresh rate in response to the trigger signal, such that the second refresh rate adapts to the first refresh rate.
Claim 38
Dependent Claim
46 words
The method of claim 32 further comprising the step of: e) coupling the controller, the counter, and the trigger to be capable of generating refreshes at a third refresh rate when the trigger is disabled, the third refresh rate being at least the first refresh rate.
Claim 39
Dependent Claim
19 words
The method of claim 33 wherein an overflow signal from the counter is generated when the trigger is disabled.
Claim 40
Dependent Claim
11 words
The method of claim 34 wherein the trigger signal is variable.
Claim 41
Dependent Claim
30 words
The method of claim 35 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each cycle of the trigger signal.
Claim 42
Dependent Claim
41 words
The method of claim 36 wherein counter providing step (b) further comprises the step of providing a state machine, the state machine for causing refreshes to be performed to cause the counter to count down in response to the trigger signal.
Claim 43
Dependent Claim
47 words
The method of claim 37 wherein timer providing step (a) further comprises the steps of: a1) providing a clock, the clock for generating a first frequency; and a2) providing a prescalar coupled to the clock, the prescalar for scaling the first frequency to the first refresh rate.
Claim 44
Independent Claim
121 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer, the timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing counting means coupled to the timer, the counting means for counting the required number of refreshes; c) providing a trigger coupled to the counter, the trigger for providing a trigger signal the trigger signal being a periodic signal; and d) providing a controller coupled to the counter, the controller for providing a plurality of refreshes at a second refresh rate in response to the trigger, such that the second refresh rate adapts to the first refresh rate.
Claim 45
Independent Claim
121 words
A method for automatically refreshing a dynamic random access memory comprising the steps of: a) providing a timer, the timer for providing a first refresh rate, the first refresh rate being a required number of refreshes for a particular interval of time; b) providing counting means coupled to the timer, the counting means for counting the required number of refreshes; c) providing a trigger coupled to the counter, the trigger for providing a trigger signal the trigger signal being a periodic signal; and d) providing a controller coupled to the counter, the controller for providing a plurality of refreshes at a second refresh rate in response to the trigger, such that the second refresh rate adapts to the first refresh rate.
Claim 46
Dependent Claim
47 words
The method of claim 39 further comprising the step of: e) coupling the counting means, the trigger, and the controller to be capable of generating refreshes at a third refresh rate when the trigger is disabled, the third refresh rate being at least the first refresh rate.
Claim 47
Dependent Claim
11 words
The method of claim 40 wherein the trigger signal is variable.
Claim 48
Dependent Claim
30 words
The method of claim 41 wherein the required number of refreshes per the particular interval of time further comprises a plurality of refreshes for each occurrence of the trigger signal.
Claim 49
Dependent Claim
23 words
The method of claim 42 wherein a signal indicating the counting means has reached the maximum count generated when the trigger is disabled.
Claim 50
Dependent Claim
33 words
The method of claim 43 wherein counting means providing step (b) further comprises the step of: b1) providing a counter coupled to the timer, the counter for counting the required number of refreshes.
Claim 51
Dependent Claim
51 words
The method of claim 44 wherein the counting means providing step (b) further comprises the step of: b2) providing a state machine coupled to the counter and the trigger, the state machine for causing refreshes to be performed to cause the counter to count down in response to the trigger signal.
Claim 52
Dependent Claim
43 words
The method of claim 45 wherein timer providing step (a) further comprises the steps of: a1) providing a clock for generating a first frequency; and a2) providing a prescalar coupled to the clock for scaling the first frequency to the first refresh rate.
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) | 2001-09-14 | 2002-03-16 | 2002-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-14 | 2006-03-16 | 2006-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-14 | 2010-03-16 | 2010-09-15 | $7700.00 | Window Closed / Lapsed |