US5506457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic switch for decoupling capacitor
Assignee: International Business Machines Corp
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Filing: 1995-04-07
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Granted: 1996-04-09
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Expires: 2015-04-07
Abstract
Abstract An electronic switch circuit switches out bad decoupling capacitors on a high speed integrated circuit chip. The circuit comprises a control device that operates in the subthreshold or off device state to detect leakage in a decoupling capacitor. This control device operates in a low impedance state if the capacitor is good and in a high impedance sate if the capacitor is bad. A feedback circuit is connected from an internal node of the capacitor to a gate of the control device so that once a state of the capacitor is detected it can be stored on the gate of the control device. A single external signal source shared by a group of capacitors activates the control device to detect leakage in the capacitor. The circuit operates to switch out capacitors that fail during normal operation.
Inventors
- 👤 Byron L. Krauter
- 👤 Peter J. Klim
- 👤 Tak H. Ning
- 👤 Stanley E. Schuster
- 👤 Lloyd A. Walls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:04
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/201; H10D84/204; H10D84/212; H03; H03K; H03K17/00; H03K17/22
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
122 words
An electronic switch for switching out bad decoupling capacitors on a high speed integrated circuit chip comprising: a control device that operates in the subthreshold or off device state to detect leakage in a decoupling capacitor, said control device operating in a low impedance state if the capacitor is good and in a high impedance sate if the capacitor is bad; a feedback circuit from an internal node of the capacitor to a gate of the control device so that once a state of the capacitor is detected it can be stored on the gate of the control device; and a single external signal source shared by a group of capacitors that activates the control device to detect leakage in the capacitor.
Claim 2
Dependent Claim
122 words
An electronic switch for switching out bad decoupling capacitors on a high speed integrated circuit chip comprising: a control device that operates in the subthreshold or off device state to detect leakage in a decoupling capacitor, said control device operating in a low impedance state if the capacitor is good and in a high impedance sate if the capacitor is bad; a feedback circuit from an internal node of the capacitor to a gate of the control device so that once a state of the capacitor is detected it can be stored on the gate of the control device; and a single external signal source shared by a group of capacitors that activates the control device to detect leakage in the capacitor.
Claim 3
Dependent Claim
24 words
The electronic switch recited in claim 1 wherein said feedback circuit comprises an inverter, said inverter switching out capacitors that fail during normal operation.
Claim 4
Dependent Claim
44 words
The electronic switch recited in claim 2 wherein said control device is an n-channel device, further comprising a second n-channel device connected between the gate of said control device and ground, said second n-channel device having a gate connected to said external signal source.
Claim 5
Dependent Claim
31 words
The electronic switch recited in claim 3 wherein said inverter comprises a p-channel device and a third n-channel device, said p-channel device having a width less than said second n-channel device.
Claim 6
Dependent Claim
55 words
The electronic switch recited in claim 4 wherein the capacitor is formed in an n-well of a chip substrate with said control device surrounding the capacitor so that leakage current paths for the capacitor are limited to paths through said control device and through a reversed biased n-well and drain junction of said control device.
Claim 7
Dependent Claim
50 words
The electronic switch recited in claim 4 further comprising a second p-channel device connected in series with said first mentioned p-channel device, said second p-channel device having a gate connected to said external signal source, said two p-channel devices and said second and third n-channel devices forming a NOR gate.
Claim 8
Dependent Claim
55 words
The electronic switch recited in claim 6 wherein the capacitor is formed in an n-well of a chip substrate with said control device surrounding the capacitor so that leakage current paths for the capacitor are limited to paths through said control device and through a reversed biased n-well and drain junction of said control device.
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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) | 1999-04-09 | 1999-10-09 | 2000-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-09 | 2003-10-09 | 2004-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-09 | 2007-10-09 | 2008-04-09 | $7700.00 | Window Closed / Lapsed |