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US4886985A Expired / Lapsed US ⏱️ 0.0 years remaining

Transistor arrangement with an output transistor

Assignee: Robert Bosch GmbH
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Filing: 1987-05-09
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Granted: 1989-12-12
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Expires: 2007-05-09
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Abstract

Abstract A transistor arrangement, particularly for the fast switching of inductive loads, includes a driving first transistor and a power output second transistor (T1, T2) interconnected as a Darlington pair having a base terminal, an emitter terminal and a collector terminal. A third transistor (T3) has its collector connected to the base of the first transistor (T1) and its emitter connected to the emitter terminal (E). A fourth transistor (T4) of a conductivity type opposite to that of the first, second and third transistors has its base connected to the collector terminal, its emitter connected to the base terminal, and its collector connected to the base of the third transistor (T3). This structure is particularly suited for a monolithic integration.

Inventors

  • 👤 Peter Flohrs
  • 👤 Klaus Heyke
  • 👤 Hartmut Michel
  • 👤 Ulrich Nelle

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 23:24
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: 5
Claim 1
Independent Claim 110 words
Transistor arrangement, particularly for the fast switching of inductive loads, comprising a first transistor (T1) and a second transistor (T2) interconnected as a Darlington pair having a base terminal, an emitter terminal and a collector terminal; a third transistor (T3) having its collector connected to the base of the first transistor (T1) and its emitter connected to the emitter terminal (E); and a fourth transistor (T4) of a conductivity type opposite to that of the first, second and third transistors and having its base connected to the collector terminal (C), its emitter connected to the base terminal (B), and its collector connected to the base of the third transistor (T3).
Claim 2
Dependent Claim 110 words
Transistor arrangement, particularly for the fast switching of inductive loads, comprising a first transistor (T1) and a second transistor (T2) interconnected as a Darlington pair having a base terminal, an emitter terminal and a collector terminal; a third transistor (T3) having its collector connected to the base of the first transistor (T1) and its emitter connected to the emitter terminal (E); and a fourth transistor (T4) of a conductivity type opposite to that of the first, second and third transistors and having its base connected to the collector terminal (C), its emitter connected to the base terminal (B), and its collector connected to the base of the third transistor (T3).
Claim 3
Dependent Claim 26 words
Transistor arrangement according to claim 1, wherein a protective resistor (R3) is connected between the collector of the third transistor (T3) and the base terminal (B).
Claim 4
Dependent Claim 24 words
Transistor arrangement according to claim 2, wherein the first transistor (T1) is a driver transistor and the second transistor (T2) is a power transistor.
Claim 5
Dependent Claim 26 words
Transistor arrangement according to claim 3, wherein an auxiliary resistor (R1, R2) is connected in parallel to each of the base-emitter diodes of the Darlington pair.

References Cited (Backward Citations)

US4128742A Cited
US4234805A Cited
US4616144A Cited
US4695807A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-12-11 1993-06-12 1993-12-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-12-11 1997-06-12 1997-12-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-12-11 2001-06-12 2001-12-12 $7700.00 Window Closed / Lapsed

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