Patent US6316987B1 successfully refreshed from Google Patents.
US6316987B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-power low-jitter variable delay timing circuit
Assignee: LSI Corp
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Filing: 1999-12-01
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Granted: 2001-11-13
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Expires: 2019-12-01
Abstract
Abstract The timing circuit includes at least one delay element and its supply voltage is obtained from an active current source. The current source is a current mirror which is driven by a differential amplifier. The differential amplifier compares a voltage on the delay clement supply line to a voltage on a current control node connected to a voltage controlled current source. An RC compensating circuit may be coupled to the current control node.
Inventors
- 👤 William J. Dally
- 👤 Ramin Farjad-Rad
- 👤 Teva J. Stone
- 👤 Xiaoying Yu
- 👤 John W. Poulton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:36
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/26; G05F3/262
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
92 words
A timing circuit comprising: a delay element; and a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current, the source circuit comprising a first transistor that sources reference current to the current control node, and a second transistor that supplies current to the delay element, the differential amplifier holding terminals of the first and second transistors at substantially the same voltage.
Claim 2
Dependent Claim
92 words
A timing circuit comprising: a delay element; and a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current, the source circuit comprising a first transistor that sources reference current to the current control node, and a second transistor that supplies current to the delay element, the differential amplifier holding terminals of the first and second transistors at substantially the same voltage.
Claim 3
Dependent Claim
16 words
The timing circuit as claimed in claim 1 wherein the differential amplifier is an operational amplifier.
Claim 4
Dependent Claim
18 words
The timing circuit as claimed in claim 2 wherein the operational amplifier has a wide output voltage swing.
Claim 5
Dependent Claim
59 words
A timing circuit comprising: a delay element; a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current; and an RC compensating circuit coupled to the current control node.
Claim 6
Dependent Claim
59 words
A timing circuit comprising: a delay element; a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current; and an RC compensating circuit coupled to the current control node.
Claim 7
Dependent Claim
103 words
A timing circuit comprising: a delay element; and a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current, the source circuit comprising a controlled current source, a first transistor in series with the controlled current source, and a second transistor supplying the current to the delay element, the current control node being between the first transistor and the current source, the differential amplifier driving the gates of the first and second transistors.
Claim 8
Dependent Claim
103 words
A timing circuit comprising: a delay element; and a source circuit supplying current to the delay element through a supply node, the source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current, the source circuit comprising a controlled current source, a first transistor in series with the controlled current source, and a second transistor supplying the current to the delay element, the current control node being between the first transistor and the current source, the differential amplifier driving the gates of the first and second transistors.
Claim 9
Dependent Claim
20 words
The timing circuit as claimed in claim 5 further comprising an RC compensating circuit coupled to the current control node.
Claim 10
Independent Claim
75 words
A method of providing power to a delay element comprising: sourcing reference current through a first transistor to a current control node; supplying current to the delay clement through a second transistor and a supply node; and comparing the voltage on the supply node to a voltage on the current control node in a differential amplifier which holds terminals of the first and second transistors at substantially the same voltage to control the supplied current.
Claim 11
Independent Claim
75 words
A method of providing power to a delay element comprising: sourcing reference current through a first transistor to a current control node; supplying current to the delay clement through a second transistor and a supply node; and comparing the voltage on the supply node to a voltage on the current control node in a differential amplifier which holds terminals of the first and second transistors at substantially the same voltage to control the supplied current.
Claim 12
Dependent Claim
15 words
The method as claimed in claim 7 wherein the differential amplifier is an operational amplifier.
Claim 13
Dependent Claim
17 words
The method as claimed in claim 8 wherein the operational amplifier has a wide output voltage swing.
Claim 14
Independent Claim
60 words
A method of providing power to a delay element comprising: supplying current to the delay element through a supply node; comparing the voltage on the supply node to a voltage on a current control node to control the supplied current; and phase compensating a current supply to the delay element with an RC circuit coupled to the current control node.
Claim 15
Independent Claim
60 words
A method of providing power to a delay element comprising: supplying current to the delay element through a supply node; comparing the voltage on the supply node to a voltage on a current control node to control the supplied current; and phase compensating a current supply to the delay element with an RC circuit coupled to the current control node.
Claim 16
Independent Claim
100 words
A method of providing power to a delay element comprising: sourcing current through a first transistor from a controlled current source; supplying current to the delay element through a second transistor and a supply node; and comparing the voltage on the supply node to a voltage on a current control node to control the supplied current, the current control node being between the first transistor and the controlled current source, the voltage on the supply node being compared to the voltage on the current control node through a differential amplifier which drives the gates of the first and second transistors.
Claim 17
Independent Claim
100 words
A method of providing power to a delay element comprising: sourcing current through a first transistor from a controlled current source; supplying current to the delay element through a second transistor and a supply node; and comparing the voltage on the supply node to a voltage on a current control node to control the supplied current, the current control node being between the first transistor and the controlled current source, the voltage on the supply node being compared to the voltage on the current control node through a differential amplifier which drives the gates of the first and second transistors.
Claim 18
Dependent Claim
21 words
The method as claimed in claim 11 further comprising compensating in an RC compensating circuit coupled to the current control node.
Claim 19
Dependent Claim
67 words
A timing circuit comprising: a delay element; a current source circuit supplying current to the delay element through a supply node, the current source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current; and a negative feedback loop from the output of the differential amplifier through the current control node.
Claim 20
Dependent Claim
67 words
A timing circuit comprising: a delay element; a current source circuit supplying current to the delay element through a supply node, the current source circuit including a differential amplifier which compares the voltage on the supply node to a voltage on a current control node to control the supplied current; and a negative feedback loop from the output of the differential amplifier through the current control node.
Claim 21
Independent Claim
56 words
A method of providing power to a delay element comprising: supplying current to the delay clement through a supply node; comparing the voltage on the supply node to a voltage on a current control node to control the supplied current; and providing negative feedback from the output of the differential amplifier through the current control node.
Claim 22
Independent Claim
56 words
A method of providing power to a delay element comprising: supplying current to the delay clement through a supply node; comparing the voltage on the supply node to a voltage on a current control node to control the supplied current; and providing negative feedback from the output of the differential amplifier through the current control node.
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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) | 2004-11-12 | 2005-05-14 | 2005-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-11-12 | 2009-05-14 | 2009-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-11-12 | 2013-05-14 | 2013-11-13 | $7700.00 | Window Closed / Lapsed |