US4021687A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor circuit for deep saturation prevention
Assignee: Hitachi Ltd
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Filing: 1975-11-05
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Granted: 1977-05-03
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Expires: 1995-11-05
Abstract
Abstract A transistor circuit which comprises a first transistor of the N-P-N type, a second transistor of the P-N-P type and a third transistor of the N-P-N type, and in which a base of the first transistor, an emitter of the second transistor and a collector of the third transistor are electrically connected with one another, while a collector of the first transistor and a base of the second transistor are electrically connected with each other, whereby the first transistor is prevented from being driven into an extremely deep saturation region.
Inventors
- 👤 Masayoshi Yoshimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:30
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/04; H03K17/042; H03K17/0422; H10; H10D; H10D84/00; H10D84/60; H10D84/63
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
98 words
A transistor circuit which comprises a first transistor of a first conductivity type, a second transistor of a second conductivity type and a third transistor of said first conductivity type, and in which a base of said first transistor, an emitter of said second transistor and a collector of said third transistor are electrically connected with one another, while a collector of said first transistor and a base of said second transistor are electrically connected with each other, and a collector of said second transistor and a base of said third transistor are electrically connected with each other.
Claim 2
Dependent Claim
98 words
A transistor circuit which comprises a first transistor of a first conductivity type, a second transistor of a second conductivity type and a third transistor of said first conductivity type, and in which a base of said first transistor, an emitter of said second transistor and a collector of said third transistor are electrically connected with one another, while a collector of said first transistor and a base of said second transistor are electrically connected with each other, and a collector of said second transistor and a base of said third transistor are electrically connected with each other.
Claim 3
Dependent Claim
26 words
The combination according to claim 1, wherein an emitter of said first transistor and an emitter of said third transistor are electrically connected with each other.
Claim 4
Dependent Claim
33 words
The combination according to claim 1, wherein said transistor circuit is a monolithic integrated circuit and said first and third transistors comprise N-P-N transistors and said second transistor comprises a lateral P-N-P transistor.
Claim 5
Dependent Claim
94 words
The combination according to claim 3, wherein said monolithic integrated circuit has at least an N-type layer, a first and a second P-type regions formed in said N-type layer, and an N +-type region formed in said first P-type region, said N-type layer serves as the collector of said first transistor and simultaneously as the base of said second transistor, said first P-type region serves as the base of said first transistor and simultaneously as the emitter of said second transistor, and said second P-type region serves as the collector of said second transistor.
Claim 6
Dependent Claim
94 words
A transistor circuit comprising: a first transistor of a first conductivity type; a second transistor of a second conductivity type, opposite said first conductivity type; and a third transistor of said first conductivity type; and wherein the base of said first transistor, the emitter of said second transistor and the collector of said third transistor are connected in common; the collector of said first transistor and the base of said second transistor are connected in common; and the collector of said second transistor and the base of said third transistor are connected in common.
Claim 7
Dependent Claim
94 words
A transistor circuit comprising: a first transistor of a first conductivity type; a second transistor of a second conductivity type, opposite said first conductivity type; and a third transistor of said first conductivity type; and wherein the base of said first transistor, the emitter of said second transistor and the collector of said third transistor are connected in common; the collector of said first transistor and the base of said second transistor are connected in common; and the collector of said second transistor and the base of said third transistor are connected in common.
Claim 8
Dependent Claim
20 words
A transistor circuit according to claim 5, wherein the emitters of said first and third transistors are connected in common.
Claim 9
Dependent Claim
33 words
The combination according to claim 6, wherein said transistor circuit is a monolithic integrated circuit and said first and third transistors comprise N-P-N transistors and said second transistor comprises a lateral P-N-P transistor.
Claim 10
Dependent Claim
94 words
The combination according to claim 7, wherein said monolithic integrated circuit has at least an N-type layer, a first and a second P-type regions formed in said N-type layer, and an N +-type region formed in said first P-type region, said N-type layer serves as the collector of said first transistor and simultaneously as the base of said second transistor, said first P-type region serves as the base of said first transistor and simultaneously as the emitter of said second transistor, and said second P-type region serves as the collector of said second transistor.
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) | 1980-05-02 | 1980-11-01 | 1981-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-02 | 1984-11-01 | 1985-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-02 | 1988-11-01 | 1989-05-03 | $7700.00 | Window Closed / Lapsed |