US6529424B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Propagation delay independent SDRAM data capture device and method
Assignee: NXP BV
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Filing: 2001-05-17
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Granted: 2003-03-04
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Expires: 2021-05-17
Abstract
Abstract A method of indicating data availability is disclosed. According to the method a data read operation is commenced for retrieving data signals based on data stored within an SDRAM. The data is provided from the SDRAM device with a first propagation delay. The SDRAM device also provides a strobe signal having a propagation delay similar to the first propagation delay. Based on the strobe signal data is latched out of the SDRAM device, as it is available to be read.
Inventors
- 👤 Dennis Koutsoures
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:23
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/401; G11C11/4063; G11C11/407; G11C11/409; G11C11/4093; G11C7/00; G06; G06F; G06F13/00; G06F13/14; G06F13/16; G06F13/1668; G06F13/1689; G11C11/4076; G11C11/4096; G11C7/10; G11C7/1006; G11C7/1051; G11C7/1072; G11C7/22; Y; Y02; Y02D; Y02D10/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
93 words
A method of indicating data availability comprising the steps of: commencing a data read operation for retrieving data signals based on data stored within a memory storage the data signals having a first propagation delay; providing a strobe signal having a propagation delay similar to the first data propagation delay from the memory device to an external circuit and returning to the memory device; and indicating data availability based on the returned strobe signal, wherein the returned signal, in response to manufacturing and environmental changes, is affected similarly to the retrieved data signals.
Claim 2
Independent Claim
93 words
A method of indicating data availability comprising the steps of: commencing a data read operation for retrieving data signals based on data stored within a memory storage the data signals having a first propagation delay; providing a strobe signal having a propagation delay similar to the first data propagation delay from the memory device to an external circuit and returning to the memory device; and indicating data availability based on the returned strobe signal, wherein the returned signal, in response to manufacturing and environmental changes, is affected similarly to the retrieved data signals.
Claim 3
Dependent Claim
22 words
A method according to claim 1 , wherein the data is latched out of the memory circuit fewer than every clock cycle.
Claim 4
Dependent Claim
15 words
A method according to claim 2 , wherein the memory is an SDRAM memory device.
Claim 5
Dependent Claim
35 words
A method according to claim 3 , wherein the SDRAM comprises a first output pad for providing the strobe signal from the SDRAM device and a second output pad for receiving the returned strobe signal.
Claim 6
Dependent Claim
131 words
A memory integrated circuit comprising: a memory storage; a plurality of data ports; a circuit for providing data signals of data read from within the memory storage to the plurality of data ports; a first strobe port; a circuit for providing a strobe signal to a circuit external the memory integrated circuit via the first strobe port, the strobe signal having similar delays to the provided data signals; a second strobe port; a circuit for receiving a returned strobe signal from the circuit external the memory integrated circuit via the second strobe port, the returned signal having a predetermined temporal relation to data availability of data retrieved from the memory storage, wherein in use the returned signal, in response to manufacturing and environmental changes, is affected similarly to the data signals.
Claim 7
Dependent Claim
131 words
A memory integrated circuit comprising: a memory storage; a plurality of data ports; a circuit for providing data signals of data read from within the memory storage to the plurality of data ports; a first strobe port; a circuit for providing a strobe signal to a circuit external the memory integrated circuit via the first strobe port, the strobe signal having similar delays to the provided data signals; a second strobe port; a circuit for receiving a returned strobe signal from the circuit external the memory integrated circuit via the second strobe port, the returned signal having a predetermined temporal relation to data availability of data retrieved from the memory storage, wherein in use the returned signal, in response to manufacturing and environmental changes, is affected similarly to the data 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) | 2006-03-03 | 2006-09-02 | 2007-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-03-03 | 2010-09-02 | 2011-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-03-03 | 2014-09-02 | 2015-03-04 | $7700.00 | Window Closed / Lapsed |