US5355123A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overheating detection circuit for detecting overheating of a power device
Assignee: Fuji Electric Co Ltd
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Filing: 1991-11-21
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Granted: 1994-10-11
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Expires: 2011-11-21
Abstract
Abstract An arrangement for detecting overheating of a power integrated circuit includes a power device integrated in a semiconductor substrate and an overheating detection circuit. The overheating detection circuit includes a reverse biased pn junction formed in the same semiconductor substrate as the power device and having a reverse leakage current flow which is temperature dependent, and a voltage converter formed in the same semiconductor substrate as the power device and coupled to the pn junction for producing a voltage depending on the reverse leakage current flow. A threshold circuit is connected for receiving the voltage and producing a signal when the voltage exceeds a threshold voltage to indicate that the power device is overheated.
Inventors
- 👤 Masaharu Nishiura
- 👤 Tatsuhiko Fujihira
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:29
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/101; H10D84/141; G; G01; G01K; G01K3/00; G01K3/005; G01K7/00; G01K7/01; G08; G08B; G08B17/00; G08B17/06; H10D84/143
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
109 words
An overheating detect ion arrangement for detecting overheating of a power integrated circuit, including: a power device integrated in a semiconductor substrate; and an overheating detection circuit, including: a reverse biased pn junction formed in the same semiconductor substrate as said power device and having a reverse leakage current flow which is temperature dependent; voltage means formed in said semiconductor substrate as said power device and coupled to said pn junction for producing a voltage depending on the reverse leakage current flow; and threshold means connected for receiving the voltage and producing a signal when the voltage exceeds a threshold voltage to indicate that said power device is overheated.
Claim 2
Dependent Claim
109 words
An overheating detect ion arrangement for detecting overheating of a power integrated circuit, including: a power device integrated in a semiconductor substrate; and an overheating detection circuit, including: a reverse biased pn junction formed in the same semiconductor substrate as said power device and having a reverse leakage current flow which is temperature dependent; voltage means formed in said semiconductor substrate as said power device and coupled to said pn junction for producing a voltage depending on the reverse leakage current flow; and threshold means connected for receiving the voltage and producing a signal when the voltage exceeds a threshold voltage to indicate that said power device is overheated.
Claim 3
Dependent Claim
21 words
The arrangement as claimed in claim 1, wherein said voltage means comprises a depletion-type MOSFET connected for receiving a constant current.
Claim 4
Dependent Claim
15 words
The arrangement as claimed in claim 1, wherein said voltage means comprises an enhancement-type MOSFET.
Claim 5
Dependent Claim
224 words
An overheating detect ion arrangement for detecting overheating of a power integrated circuit, including: a power device integrated in a semiconductor substrate; and an overheating detection circuit comprising: first and second temperature detecting circuits, said first temperature detecting circuit having a first temperature threshold and said second temperature detecting circuit having a second temperature threshold lower than the first temperature threshold, each of said first and second temperature detecting circuits including: a reverse biased pn junction formed in the same semiconductor substrate as said power device and having a reverse leakage current flow which is temperature dependent; voltage means formed in the same semiconductor substrate as said power device and coupled to said pn junction for producing a voltage depending on the reverse leakage current flow; and threshold means connected to said voltage means for receiving the voltage and producing a signal when the voltage exceeds a threshold voltage corresponding to the respective threshold temperature; and hysteresis means receiving the signals produced by the respective threshold means of said first and second temperature detecting circuits for producing an overheating signal in response to the signal from the threshold means of said first temperature detecting circuit indicating that said power device is overheated and continuing to produce the overheating signal until the signal from the threshold means of said second temperature detecting circuit is discontinued.
Claim 6
Dependent Claim
224 words
An overheating detect ion arrangement for detecting overheating of a power integrated circuit, including: a power device integrated in a semiconductor substrate; and an overheating detection circuit comprising: first and second temperature detecting circuits, said first temperature detecting circuit having a first temperature threshold and said second temperature detecting circuit having a second temperature threshold lower than the first temperature threshold, each of said first and second temperature detecting circuits including: a reverse biased pn junction formed in the same semiconductor substrate as said power device and having a reverse leakage current flow which is temperature dependent; voltage means formed in the same semiconductor substrate as said power device and coupled to said pn junction for producing a voltage depending on the reverse leakage current flow; and threshold means connected to said voltage means for receiving the voltage and producing a signal when the voltage exceeds a threshold voltage corresponding to the respective threshold temperature; and hysteresis means receiving the signals produced by the respective threshold means of said first and second temperature detecting circuits for producing an overheating signal in response to the signal from the threshold means of said first temperature detecting circuit indicating that said power device is overheated and continuing to produce the overheating signal until the signal from the threshold means of said second temperature detecting circuit is discontinued.
Claim 7
Dependent Claim
22 words
The arrangement as claimed in claim 4, wherein each said voltage means comprises a depletion-type MOSFET connected for receiving a constant current.
Claim 8
Dependent Claim
16 words
The arrangement as claimed in claim 4, wherein each said voltage means comprises an enhancement-type MOSFET.
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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) | 1997-10-10 | 1998-04-11 | 1998-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-10 | 2002-04-11 | 2002-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-10 | 2006-04-11 | 2006-10-11 | $7700.00 | Window Closed / Lapsed |