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US4536702A Expired / Lapsed US ⏱️ 0.0 years remaining

Constant current source or voltage source transistor circuit

Assignee: Toshiba Corp
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Filing: 1983-04-05
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Granted: 1985-08-20
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Expires: 2003-04-05
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Abstract

Abstract According to this invention, a transistor circuit is disclosed which comprises two main circuit portions connected in parallel between a power supply terminal and a reference voltage terminal. They are responsive to the power supply voltage to generate first and second currents respectively when the power supply voltage exceeds predetermined first and second voltage levels respectively. A circuit portion is also provided for producing a constant current equivalent to the difference of said first and second currents.

Inventors

  • 👤 Katsumi Nagano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 16:47
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/22; G05F3/222; G05F3/227

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 233 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said power supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels wherein said first circuit portion includes first, second and third resistor means connected in series between said first and said second terminal, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected between said second and third resistor means, and a collector electrode connected between said first and second resistor means, said second circuit portion comprises fourth resistor means having first and second ends, said first end being connected to said first terminal, diode means connected in series between said second end of said fourth resistor means and said second terminal; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents, said circuit means including second transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said base electrode of said first transistor means, and a collector electrode connected to said second end of said fourth resistor means.
Claim 2
Dependent Claim 233 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said power supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels wherein said first circuit portion includes first, second and third resistor means connected in series between said first and said second terminal, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected between said second and third resistor means, and a collector electrode connected between said first and second resistor means, said second circuit portion comprises fourth resistor means having first and second ends, said first end being connected to said first terminal, diode means connected in series between said second end of said fourth resistor means and said second terminal; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents, said circuit means including second transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said base electrode of said first transistor means, and a collector electrode connected to said second end of said fourth resistor means.
Claim 3
Dependent Claim 252 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said power supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels, wherein said first circuit portion includes first resistor means having first and second ends, said first end being connected to said first terminal, first and second diode means connected in series between said second end of said first resistor means and said second terminal, said second circuit portion comprises second resistor means having first and second ends, said first end being connected to said first terminal, third resistor means having first and second ends, said first end being connected to said second end of said second resistor means, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said second end of said second resistor means, a collector electrode connected to said second end of said third resistor means, second transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said second end of said third resistor means, a collector electrode connected to an output terminal; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents.
Claim 4
Dependent Claim 252 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said power supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels, wherein said first circuit portion includes first resistor means having first and second ends, said first end being connected to said first terminal, first and second diode means connected in series between said second end of said first resistor means and said second terminal, said second circuit portion comprises second resistor means having first and second ends, said first end being connected to said first terminal, third resistor means having first and second ends, said first end being connected to said second end of said second resistor means, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said second end of said second resistor means, a collector electrode connected to said second end of said third resistor means, second transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said second end of said third resistor means, a collector electrode connected to an output terminal; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents.
Claim 5
Dependent Claim 235 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels, wherein said first circuit portion comprises first resistor means having first and second ends, said first end being connected to said first terminal, first and second diode means connected in series between said second end of said first resistor means and said second terminal, said second circuit portion comprises second, third and fourth resistor means connected in series between said first and second terminals, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected to a connection of said third and fourth resistor means, and a collector electrode connected between said second and third resistor means; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents, said circuit means including second transistor means having an emitter electrode connected to said second terminal, a base electrode connected between said first and second diode means, and a collector electrode connected to said collector electrode of said first transistor means.
Claim 6
Dependent Claim 235 words
A transistor circuit having first and second terminals driven by a power supply voltage applied across the terminals comprising: first and second circuit portions connected in parallel between said first and second terminals, said first and second circuit portions responsive to said supply voltage to cause respective first and second currents proportional to said power supply voltage when said power supply voltage exceeds respective first and second predetermined voltage levels, wherein said first circuit portion comprises first resistor means having first and second ends, said first end being connected to said first terminal, first and second diode means connected in series between said second end of said first resistor means and said second terminal, said second circuit portion comprises second, third and fourth resistor means connected in series between said first and second terminals, first transistor means having an emitter electrode connected to said second terminal, a base electrode connected to a connection of said third and fourth resistor means, and a collector electrode connected between said second and third resistor means; and circuit means connected to said first and second circuit portions for producing a differential current of said first and second currents, said circuit means including second transistor means having an emitter electrode connected to said second terminal, a base electrode connected between said first and second diode means, and a collector electrode connected to said collector electrode of said first transistor means.
Claim 7
Dependent Claim 81 words
A transistor circuit according to claim 2, which further comprises third transistor means having an emitter electrode connected to an output terminal, a base electrode connected to the collector electrode of said first transistor means, a collector electrode connected to said first terminal, fourth transistor means having an emitter electrode connected to said second terminal, a base electrode connected to said base electrode of said first transistor means, a collector electrode connected to said emitter electrode of said third transistor means.

References Cited (Backward Citations)

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US4030023A Cited
GB2007055A Cited
US4221979A Cited
GB2010623A Cited
GB2030810A Cited
DE3023119A1 Cited
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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) 1988-08-19 1989-02-18 1989-08-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-08-19 1993-02-18 1993-08-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-08-19 1997-02-18 1997-08-20 $7700.00 Window Closed / Lapsed

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