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US5091689A Expired / Lapsed US ⏱️ 0.0 years remaining

Constant current circuit and integrated circuit having said circuit

Assignee: Canon Inc
•
Filing: 1990-07-16
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Granted: 1992-02-25
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Expires: 2010-07-16
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Abstract

Abstract A constant current circuit comprises a junction type field effect transistor and a bipolar transistor. The channel forming region of the junction type field effect transistor and the base region of the bipolar transistor are constituted to be common to each other.

Inventors

  • 👤 Shuichi Katao

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 01:25
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 37 words
A constant current circuit comprising: a junction type field effect transistor comprising a channel forming region; and a bipolar transistor comprising a base region, said channel forming region and said base region being common to each other.
Claim 2
Dependent Claim 37 words
A constant current circuit comprising: a junction type field effect transistor comprising a channel forming region; and a bipolar transistor comprising a base region, said channel forming region and said base region being common to each other.
Claim 3
Dependent Claim 30 words
A constant current circuit according to claim 1, wherein said junction type field effect transistor and said bipolar transistor are formed in a common region surrounded by an isolation region.
Claim 4
Dependent Claim 43 words
A constant current circuit according to claim 1, wherein said junction type field effect transistor further comprises a gate region, wherein said bipolar transistor further comprises a collector region, and wherein said gate region and said collector region are common to each other.
Claim 5
Dependent Claim 108 words
A circuit device comprising: a bipolar transistor comprising, a collector region of a first conductivity type, a base region of a second conductivity type opposite to the first conductivity type, and an emitter region of the first conductivity type; and a junction type field effect transistor comprising, a gate region of the first conductivity type electrically connected to said collector region, a source region, and a drain region of the second conductivity type, wherein said source region and said drain region are provided in contact with said base region of said bipolar transistor, and wherein said gate region is disposed between said drain region and said source region.
Claim 6
Dependent Claim 108 words
A circuit device comprising: a bipolar transistor comprising, a collector region of a first conductivity type, a base region of a second conductivity type opposite to the first conductivity type, and an emitter region of the first conductivity type; and a junction type field effect transistor comprising, a gate region of the first conductivity type electrically connected to said collector region, a source region, and a drain region of the second conductivity type, wherein said source region and said drain region are provided in contact with said base region of said bipolar transistor, and wherein said gate region is disposed between said drain region and said source region.
Claim 7
Dependent Claim 30 words
A circuit device according to claim 4, wherein said bipolar transistor comprises a high resistance region of the first conductivity type disposed between said base region and said collector region.
Claim 8
Dependent Claim 36 words
A circuit device according to claim 4, wherein said collector region of said bipolar transistor and said gate region of said junction type field effect transistor are disposed in continuous regions of a same conductivity type.
Claim 9
Dependent Claim 15 words
A circuit device according to claim 4, wherein said first conductivity type is n type.
Claim 10
Dependent Claim 15 words
A circuit device according to claim 4, wherein said first conductivity type is p type.
Claim 11
Dependent Claim 31 words
A circuit device according to claim 4, wherein at least one of said source region and said drain region is a contact region for said base region of said bipolar transistor.

References Cited (Backward Citations)

US3303413A Cited
US4678936A Cited
US4891533A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-02-24 1995-08-26 1996-02-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-02-24 1999-08-26 2000-02-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-02-24 2003-08-26 2004-02-25 $7700.00 Window Closed / Lapsed

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