Patent US6091283A successfully refreshed from Google Patents.
US6091283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sub-threshold leakage tuning circuit
Assignee: Sun Microsystems Inc
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Filing: 1998-02-24
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Granted: 2000-07-18
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Expires: 2018-02-24
Abstract
Abstract To compensate for process, activity and temperature-induced device threshold variations in a semiconductor circuit having a transistor, a potential of the gate the transistor is held to a preset subthreshold potential, and a channel current of the channel region is compared with a reference current to obtain a comparison result. A bias potential of a substrate is adjusted according to the comparison result to hold the subthreshold current at the reference current.
Inventors
- 👤 James E. Murgula
- 👤 James B. Burr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:03
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/205
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
112 words
A semiconductor circuit comprising: a transistor having a drain, a source, a channel region, a bulk and a gate; first voltage sources which respectively hold a first potential across said gate and said source and a second potential across said drain and said source to values at which a drain-to-source current through said channel is subthreshold; a current source which outputs a reference current; a comparator which compares the reference current with the subthreshold drain-to-source current through said channel; and a second voltage source which adjusts a bias potential of said bulk according to an output of said comparator to hold the subthreshold drain-to-source current through said channel at the reference current.
Claim 2
Dependent Claim
112 words
A semiconductor circuit comprising: a transistor having a drain, a source, a channel region, a bulk and a gate; first voltage sources which respectively hold a first potential across said gate and said source and a second potential across said drain and said source to values at which a drain-to-source current through said channel is subthreshold; a current source which outputs a reference current; a comparator which compares the reference current with the subthreshold drain-to-source current through said channel; and a second voltage source which adjusts a bias potential of said bulk according to an output of said comparator to hold the subthreshold drain-to-source current through said channel at the reference current.
Claim 3
Dependent Claim
24 words
A semiconductor circuit as claimed in claim 1, wherein said transistor is an n-channel transistor, and wherein the first potential is a negative potential.
Claim 4
Dependent Claim
46 words
A semiconductor circuit as claimed in claim 1, wherein said first potential is between -500 mV and -50 mV, wherein said reference current is between 0.01 and 100 nA, and wherein a threshold voltage of the transistor is less than the first potential plus 500 mV.
Claim 5
Dependent Claim
24 words
A semiconductor circuit as claimed in claim 1, wherein said transistor is a p-channel transistor, and wherein the first potential is a positive potential.
Claim 6
Dependent Claim
46 words
A semiconductor circuit as claimed in claim 4, wherein said first potential is between +500 mV and +50 mV, wherein said reference current is between -0.01 and -100 nA, and wherein a threshold voltage of the transistor is more than the first potential minus 500 mV.
Claim 7
Independent Claim
107 words
A method for compensating for temperature variations in a semiconductor circuit having a transistor, the transistor having a drain, a source, a channel region, a bulk and a gate, said method comprising: holding a first potential across the gate and the source and a second potential across the drain and the source to preset potentials at which a drain-to-source current through said channel is subthreshold; comparing a drain-to-source channel current of the channel region with a reference current to obtain a comparison result; and, adjusting a bias potential of the bulk according to the comparison result to hold the subthreshold drain-to-source channel current at the reference current.
Claim 8
Independent Claim
107 words
A method for compensating for temperature variations in a semiconductor circuit having a transistor, the transistor having a drain, a source, a channel region, a bulk and a gate, said method comprising: holding a first potential across the gate and the source and a second potential across the drain and the source to preset potentials at which a drain-to-source current through said channel is subthreshold; comparing a drain-to-source channel current of the channel region with a reference current to obtain a comparison result; and, adjusting a bias potential of the bulk according to the comparison result to hold the subthreshold drain-to-source channel current at the reference current.
Claim 9
Dependent Claim
23 words
A method as claimed in claim 6, wherein said transistor is an n-channel transistor, and wherein the first potential is a negative potential.
Claim 10
Dependent Claim
45 words
A method as claimed in claim 7, wherein said first potential is between -500 mV and -50 mV, wherein said reference current is between 0.01 and 100 nA, and wherein a threshold voltage of said transistor is less than the first potential plus 500 mV.
Claim 11
Dependent Claim
24 words
A semiconductor circuit as claimed in claim 6, wherein said transistor is a p-channel transistor, and wherein the first potential is a positive potential.
Claim 12
Dependent Claim
46 words
A semiconductor circuit as claimed in claim 9, wherein said first potential is between 500 mV and 50 mV, wherein said reference current is between -0.01 and -100 nA, and wherein a threshold voltage is less than more than the the first potential minus 500 mV.
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) | 2003-07-18 | 2004-01-17 | 2004-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-18 | 2008-01-17 | 2008-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-18 | 2012-01-17 | 2012-07-18 | $7700.00 | Window Closed / Lapsed |