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US4604568A Expired / Lapsed US ⏱️ 0.0 years remaining

Current source with adjustable temperature coefficient

Assignee: NXP USA Inc
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Filing: 1984-10-01
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Granted: 1986-08-05
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Expires: 2004-10-01
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Abstract

Abstract In a circuit arrangement for providing a current having a controllable temperature coefficient of current, a diffused resistor (334) is used to set up a reference current in a current source (40) which has a temperature coefficient dependent upon the diffused resistor. A current mirror (352, 354, 356) receives the reference current and passes a portion of it through an ion implanted resistor (360). The output current has a temperature coefficient which is a function of the original temperature coefficient of current and a nonzero algebraic multiple of the temperature coefficient of the implanted resistor. By appropriate selection of the resistor values and types, the temperature coefficient of the output current can be set to any desired value.

Inventors

  • 👤 Yolanda Prieto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 06:21
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/04; H03D; H03D3/00; G; G05; G05F; G05F1/00; G05F1/10; G05F1/46; G05F1/462; G05F1/463; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/30; H03F1/00; H03F1/30; H03F1/302; Y; Y10; Y10S; Y10S323/00; Y10S323/907

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 146 words
In a monolithic integrated circuit, a circuit arrangement for providing a current having a controlled variation with temperature comprising: a first resistive pattern area having a first predetermined temperature coefficient of resistivity; a current source coupled to said first resistive pattern area for supplying a first current having a first temperature coefficient of current which is a function of said first predetermined temperature coefficient of resistivity; a current mirror receiving said first current as its reference current and producing a mirror current; and a second resistive pattern area having a second predetermined temperature coefficient of resistivity, which is different from said first temperature coefficient of resistivity, said second resistive pattern area being coupled to said current mirror, whereby said mirror current has a controlled variation with temperature characterized by a temperature coefficient which is a function of said first and second predetermined temperature coefficients of resistivity.
Claim 2
Dependent Claim 146 words
In a monolithic integrated circuit, a circuit arrangement for providing a current having a controlled variation with temperature comprising: a first resistive pattern area having a first predetermined temperature coefficient of resistivity; a current source coupled to said first resistive pattern area for supplying a first current having a first temperature coefficient of current which is a function of said first predetermined temperature coefficient of resistivity; a current mirror receiving said first current as its reference current and producing a mirror current; and a second resistive pattern area having a second predetermined temperature coefficient of resistivity, which is different from said first temperature coefficient of resistivity, said second resistive pattern area being coupled to said current mirror, whereby said mirror current has a controlled variation with temperature characterized by a temperature coefficient which is a function of said first and second predetermined temperature coefficients of resistivity.
Claim 3
Dependent Claim 16 words
The circuit of claim 1, wherein said first resistive pattern area further comprises a diffused resistor.
Claim 4
Dependent Claim 16 words
The circuit of claim 1, wherein said first resistive pattern area further comprises an implanted resistor.
Claim 5
Dependent Claim 22 words
The circuit of claim 1, wherein said first resistive pattern area further comprises a resistive element external to the monolithic integrated circuit.
Claim 6
Dependent Claim 13 words
The circuit of claim 4, wherein said external resistive element includes a thermistor.
Claim 7
Dependent Claim 16 words
The circuit of claim 1, wherein said second resistive pattern area further comprises a diffused resistor.
Claim 8
Dependent Claim 16 words
The circuit of claim 1, wherein said second resistive pattern area further comprises an implanted resistor.
Claim 9
Dependent Claim 22 words
The circuit of claim 1, wherein said second resistive pattern area further comprises a resistive element external to the monolithic integrated circuit.
Claim 10
Dependent Claim 13 words
The circuit of claim 8, wherein said external resistive element includes a thermistor.
Claim 11
Dependent Claim 133 words
A circuit arrangement for providing a current having a controlled temperature coefficient, said circuit arrangement comprising: a first resistive means having a first predetermined temperature coefficient; current source means coupled to said first resistive means for supplying a first current having a first temperature coefficient which is dependent upon said first predetermined temperature coefficient; current mirror means receiving said first current as its reference current and producing a mirror current; and a second resistive means having a second predetermined temperature coefficient which is different in value from said first temperature coefficient, said second resistive means being coupled to said current mirror means, whereby said mirror current has a temperature coefficient which is dependent upon a combination of said first predetermined temperature coefficient and a non-zero algebraic multiple of said second predetermined temperature coefficient.
Claim 12
Dependent Claim 133 words
A circuit arrangement for providing a current having a controlled temperature coefficient, said circuit arrangement comprising: a first resistive means having a first predetermined temperature coefficient; current source means coupled to said first resistive means for supplying a first current having a first temperature coefficient which is dependent upon said first predetermined temperature coefficient; current mirror means receiving said first current as its reference current and producing a mirror current; and a second resistive means having a second predetermined temperature coefficient which is different in value from said first temperature coefficient, said second resistive means being coupled to said current mirror means, whereby said mirror current has a temperature coefficient which is dependent upon a combination of said first predetermined temperature coefficient and a non-zero algebraic multiple of said second predetermined temperature coefficient.
Claim 13
Dependent Claim 14 words
The circuit of claim 10, wherein said first resistive means includes a diffused resistor.
Claim 14
Dependent Claim 14 words
The circuit of claim 10, wherein said first resistive means includes an implanted resistor.
Claim 15
Dependent Claim 15 words
The circuit of claim 10, wherein said first resistive means includes an external resistive element.
Claim 16
Dependent Claim 13 words
The circuit of claim 13, wherein said external resistive element includes a thermistor.
Claim 17
Dependent Claim 14 words
The circuit of claim 10, wherein said second resistive means includes a diffused resistor.
Claim 18
Dependent Claim 14 words
The circuit of claim 10, wherein said second resistive means includes an implanted resistor.
Claim 19
Dependent Claim 15 words
The circuit of claim 10, wherein said second resistive means includes an external resistive element.
Claim 20
Dependent Claim 13 words
The circuit of claim 17, wherein said external resistive element includes a thermistor.
Claim 21
Dependent Claim 16 words
The circuit of claim 7 wherein said current mirror means includes a current multiplying current mirror.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-08-04 1990-02-03 1990-08-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-08-04 1994-02-03 1994-08-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-08-04 1998-02-03 1998-08-05 $7700.00 Window Closed / Lapsed

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