US4450515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bias-voltage generator
Assignee: Fujitsu Ltd
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Filing: 1982-06-14
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Granted: 1984-05-22
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Expires: 2002-06-14
Abstract
Abstract A bias-voltage generator suitable for measuring a substrate leakage current is disclosed. The bias-voltage generator comprises of an oscillator, a charge-pumping circuit which is driven by the oscillator via a pumping capacitor, and a charge-pumping switch. The charge-pumping switch is connected in series with the charge-pumping circuit. The charge-pumping switch cooperates with an external electrode for controlling the ON or OFF condition of the charge pumping circuit. The charge-pumping switch is turned OFF by the external electrode becoming a floating state and a resistor employed to ensure the charge pumping switch is inoperable after the above-mentioned measurement is completed and the circuit is shipped from the factory.
Inventors
- 👤 Yoshihiro Takemae
- 👤 Tomio Nakano
- 👤 Masao Nakano
- 👤 Norihisa Tsuge
- 👤 Tsuyoshi Ohira
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:33
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/205
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
109 words
A bias-voltage generator having a first and second power sources operatively connectable thereto and applying a bias voltage to a semiconductor substrate having a MOS integrated circuit, comprising: an oscillator operatively connectable to the first and second power sources; a charge-pumping circuit operatively connected to the first power source, having a one-way charge path formed between the first power source and the semiconductor substrate and being driven by said oscillator; a charge-pumping switch, operatively connected between said charge pumping circuit and the semiconductor substrate, in said one-way charge path; and an external electrode, operatively connected to said charge-pumping switch, for controlling the ON or OFF of said charge-pumping switch.
Claim 2
Dependent Claim
109 words
A bias-voltage generator having a first and second power sources operatively connectable thereto and applying a bias voltage to a semiconductor substrate having a MOS integrated circuit, comprising: an oscillator operatively connectable to the first and second power sources; a charge-pumping circuit operatively connected to the first power source, having a one-way charge path formed between the first power source and the semiconductor substrate and being driven by said oscillator; a charge-pumping switch, operatively connected between said charge pumping circuit and the semiconductor substrate, in said one-way charge path; and an external electrode, operatively connected to said charge-pumping switch, for controlling the ON or OFF of said charge-pumping switch.
Claim 3
Dependent Claim
104 words
A bias-voltage generator as set forth in claim 1, wherein said charge pumping circuit comprises a pair of MOS transistors operatively connected to said first power source, wherein said charge-pumping switch comprises a MOS transistor operatively connected to said pair of MOS transistors of said charge pumping circuit and having a gate, and wherein said one-way charge-pumping path comprises: said pair of MOS transistors connected in series comprising said charge-pumping circuit; said MOS transistor of said charge-pumping switch in series with said pair of MOS transistors of said charge pumping circuit; and an external conductor electrically connected to the bottom of the semiconductor substrate.
Claim 4
Dependent Claim
27 words
A bias-voltage generator as set forth in claim 2, wherein the gate of said MOS transistor of said charge-pumping switch is operatively connected to said external electrode.
Claim 5
Dependent Claim
51 words
A bias-voltage generator as set forth in claim 3, further comprising a resistor operatively connected to the first power source and the gate of said charge-pumping switch, and wherein the gate of said transistor of said charge-pumping switch is operatively connected to the first power source by way of said resistor.
Claim 6
Dependent Claim
31 words
A bias-voltage generator as set forth in claim 3, further comprising a resistor operatively connected between the gate of said MOS transistor of said charge-pumping switch and the second power source.
Claim 7
Dependent Claim
51 words
A bias-voltage generator applying a bias voltage to a semiconductor substrate, comprising: an oscillator operatively connected to first and second power sources; a charge pumping circuit operatively connected to the first power source and said oscillator; and a charge-pumping switch operatively connected between said charge pumping circuit and the semiconductor substrate.
Claim 8
Dependent Claim
51 words
A bias-voltage generator applying a bias voltage to a semiconductor substrate, comprising: an oscillator operatively connected to first and second power sources; a charge pumping circuit operatively connected to the first power source and said oscillator; and a charge-pumping switch operatively connected between said charge pumping circuit and the semiconductor substrate.
Claim 9
Dependent Claim
45 words
A bias-voltage generator as set forth in claim 6, wherein said charge pumping circuit comprises: a first transistor operatively connected to said oscillator and the first power source; and a second transistor operatively connected to said first transistor, said oscillator and said charge pumping switch.
Claim 10
Dependent Claim
28 words
A bias-voltage generator as set forth in claim 7, wherein said charge pumping switch comprises a third transistor operatively connected to said second transistor and the semiconductor substrate.
Claim 11
Dependent Claim
24 words
A bias-voltage generator as set forth in claim 8, further comprising a resistor operatively connected between the second power source and said third transistor.
Claim 12
Dependent Claim
24 words
A bias-voltage generator as set forth in claim 8, further comprising a resistor operatively connected between the first power source and said third transistor.
Claim 13
Dependent Claim
25 words
A bias-voltage generator as set forth in claim 9, further comprising a capacitor operatively connected to said oscillator, said first transistor and said second transistor.
Claim 14
Dependent Claim
29 words
A bias-voltage generator as set forth in claim 11, further comprising an external electrode operatively connected to said third transistor and mounted on the surface of the semiconductor substrate.
Claim 15
Dependent Claim
25 words
A bias-voltage generator as set forth in claim 10, further comprising a capacitor operatively connected to said oscillator, said first transistor and said second transistor.
Claim 16
Dependent Claim
29 words
A bias-voltage generator as set forth in claim 13, further comprising an external electrode operatively connected to said third transistor and mounted on the surface of the semiconductor substrate.
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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) | 1987-05-22 | 1987-11-21 | 1988-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-22 | 1991-11-21 | 1992-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-22 | 1995-11-21 | 1996-05-22 | $7700.00 | Window Closed / Lapsed |