US5027006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for detecting a supply voltage drop and for resetting an initialization circuit
Assignee: STMicroelectronics SA
•
Filing: 1989-12-21
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Granted: 1991-06-25
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Expires: 2009-12-21
Abstract
Abstract A circuit detecting the drop of a supply voltage applied between a high voltage supply terminal and a low voltage supply terminal for an integrated circuit. A trheshold circuit includes an input terminal connected to the high voltage supply terminal, an output terminal supplying a desired signal and threshold supply terminals. A MOS capacitor is connected between the low voltage supply terminal and an N-channel MOS transistor. The drain and gate of the transistor are connected together and to the high voltage supply terminal. The threshold supply terminals are connected across the capacitor.
Inventors
- 👤 Olivier Queinnec
- 👤 Henri Pouget
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:42
CPC Classifications
H; H03; H03K; H03K19/00; H03K17/00; H03K17/22; H03K17/223; G; G01; G01R; G01R19/00; G01R19/165; G01R19/16504; G01R19/16519
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
108 words
A circuit for detecting a voltage drop of an integrated circuit supply voltage supplied between a high voltage supply terminal and a low voltage supply terminal, comprising: a threshold circuit comprising an input terminal connected to the high voltage supply terminal, an output terminal, and threshold circuit supply terminals, a MOS capacitor having first and second terminals connected across said threshold circuit supply terminals, said first terminal being connected to the low voltage supply terminal, and an N-channel MOS transistor, having a source connected to said second terminal of said capacitor and having a drain and gate interconnected to each other and to the high voltage supply terminal.
Claim 2
Dependent Claim
108 words
A circuit for detecting a voltage drop of an integrated circuit supply voltage supplied between a high voltage supply terminal and a low voltage supply terminal, comprising: a threshold circuit comprising an input terminal connected to the high voltage supply terminal, an output terminal, and threshold circuit supply terminals, a MOS capacitor having first and second terminals connected across said threshold circuit supply terminals, said first terminal being connected to the low voltage supply terminal, and an N-channel MOS transistor, having a source connected to said second terminal of said capacitor and having a drain and gate interconnected to each other and to the high voltage supply terminal.
Claim 3
Dependent Claim
14 words
A detection circuit according to claim 1 wherein said threshold circuit comprises an inverter.
Claim 4
Dependent Claim
28 words
A detecting circuit according to claim 1 wherein said output terminal is connected to an initialization circuit for resetting said initialization circuit while powering a MOS integrated circuit.
Claim 5
Dependent Claim
98 words
A detection circuit according to claim 3 wherein said initialization circuit comprises a second N-channel MOS transistor having a source connected to the low voltage supply terminal, a drain connected to the high voltage supply terminal through an impedance and to an output terminal, and a gate connected to the gate/drain connection of a P-channel MOS transistor, the source of said P-channel MOS transistor being connected to the high voltage supply terminal, and further comprising: means for shorting the gate and the source of said second N-channel MOS transistor in response to a signal at said output terminal.
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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) | 1994-06-24 | 1994-12-24 | 1995-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-24 | 1998-12-24 | 1999-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-24 | 2002-12-24 | 2003-06-25 | $7700.00 | Window Closed / Lapsed |