Patent US4460865A successfully refreshed from Google Patents.
US4460865A
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US
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Variable temperature coefficient level shifting circuit and method
Assignee: Motorola Solutions Inc
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Filing: 1982-08-30
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Granted: 1984-07-17
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Expires: 2002-08-30
Abstract
Abstract A variable temperature coefficient level shifter includes a circuit which generates a voltage V BE having a negative temperature coefficient and a voltage ΔV BE having a positive temperature coefficient. A control current is generated by placing a first resistor between V BE and ground and a second resistor between ΔV BE and ground. Each of these currents forms a component of the control current which then has some net temperature coefficient. By properly scaling the resistors the control current may have any desired temperature coefficient between 2800 ppm and 3000 ppm. Once the temperature coefficient is set, a third resistor is provided through which the control current flows. The amplitude of the shift is then selected by selecting the value of resistor R S .
Inventors
- 👤 Byron G. Bynum
- 👤 Randall C. Gray
- 👤 Robert B. Jarrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:40
CPC Classifications
G; G05; G05F; G05F3/00; G05F3/02; G05F3/08; G05F3/10; G05F3/16; G05F3/20; G05F3/30; Y; Y10; Y10S; Y10S323/00; Y10S323/907
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
130 words
A level shifting circuit for producing an output voltage having a desired amplitude and temperature coefficient, comprising: a first supply voltage terminal; a second supply voltage terminal; a first current source coupled to said first supply voltage terminal for generating a first current having a positive temperature coefficient; a second current source coupled to said first supply voltage terminal for generating a second current having a negative temperature coefficient; and first resistive means coupled between said first and second current sources and said second supply voltage terminal for combining said first and second currents to produce a third current having a net temperature coefficient corresponding to said desired temperature coefficient and for generating from said third current a voltage having said net temperature coefficient, said voltage having said desired amplitude.
Claim 2
Dependent Claim
130 words
A level shifting circuit for producing an output voltage having a desired amplitude and temperature coefficient, comprising: a first supply voltage terminal; a second supply voltage terminal; a first current source coupled to said first supply voltage terminal for generating a first current having a positive temperature coefficient; a second current source coupled to said first supply voltage terminal for generating a second current having a negative temperature coefficient; and first resistive means coupled between said first and second current sources and said second supply voltage terminal for combining said first and second currents to produce a third current having a net temperature coefficient corresponding to said desired temperature coefficient and for generating from said third current a voltage having said net temperature coefficient, said voltage having said desired amplitude.
Claim 3
Dependent Claim
39 words
A circuit according to claim 1 wherein said first current source comprises: first means for generating a first voltage having a positive temperature coefficient; and second resistive means coupled between said first means and said first supply voltage terminal.
Claim 4
Dependent Claim
38 words
A circuit according to claim 2 wherein said second current source comprises: second means for generating a voltage having a negative temperature coefficient; and third resistive means coupled between said second means and said first supply voltage terminal.
Claim 5
Dependent Claim
35 words
A circuit according to claim 3 wherein said second current corresponds to the base emitter voltage of a transistor and wherein said first current corresponds to the base-emitter voltage differential of a pair of transistors.
Claim 6
Dependent Claim
153 words
A level shifting circuit for coupling to a first source of a first voltage having a positive temperature coefficient and to a second source of a second voltage having a negative temperature coefficient for the purpose of producing a voltage having a desired temperature coefficient and amplitude, comprising: a first supply voltage terminal; a second supply voltage terminal; first resistive means coupled between said first supply voltage terminal and said first source for generating a first current having a positive temperature coefficient; second resistive means coupled between said first supply voltage terminal and said second source for generating a second current having a negative temperature coefficient; and third resistive means coupled between said second supply voltage terminal and said first and second sources for combining said first and second currents to produce a third current having a net temperature coefficient and for generating therefrom a voltage having a desired amplitude and temperature coefficient.
Claim 7
Dependent Claim
153 words
A level shifting circuit for coupling to a first source of a first voltage having a positive temperature coefficient and to a second source of a second voltage having a negative temperature coefficient for the purpose of producing a voltage having a desired temperature coefficient and amplitude, comprising: a first supply voltage terminal; a second supply voltage terminal; first resistive means coupled between said first supply voltage terminal and said first source for generating a first current having a positive temperature coefficient; second resistive means coupled between said first supply voltage terminal and said second source for generating a second current having a negative temperature coefficient; and third resistive means coupled between said second supply voltage terminal and said first and second sources for combining said first and second currents to produce a third current having a net temperature coefficient and for generating therefrom a voltage having a desired amplitude and temperature coefficient.
Claim 8
Independent Claim
81 words
A method for providing controllable voltage level shift having an independently controllable temperature coefficient, comprising: generating a first voltage having a positive temperature coefficient; generating a second voltage having a negative temperature coefficient; applying said first and second voltages across first and second resistive means the values of which are chosen to result in a current having a desired net temperature coefficient; and applying said total current to a third resistive means the resistance of which determines said voltage level shift.
Claim 9
Independent Claim
81 words
A method for providing controllable voltage level shift having an independently controllable temperature coefficient, comprising: generating a first voltage having a positive temperature coefficient; generating a second voltage having a negative temperature coefficient; applying said first and second voltages across first and second resistive means the values of which are chosen to result in a current having a desired net temperature coefficient; and applying said total current to a third resistive means the resistance of which determines said voltage level shift.
Claim 10
Dependent Claim
32 words
A method according to claim 6 further including: varying said first and second resistive means to varying said net temperature coefficient; and varying said third resistive means to alter said level shift.
Claim 11
Dependent Claim
26 words
A method according to claim 7 wherein said net temperature coefficient may be varied from approximately -2800 parts per million to approximately +3000 parts per million.
Claim 12
Independent Claim
86 words
A method for level shifting a voltage, the amplitude of the level shift and the temperature coefficient thereof being independently controllable, comprising: generating a first current having a positive temperature coefficient; generating a second current having a negative temperature coefficient; varying the magnitude of said first and second currents to achieve a net negative, zero, or positive temperature coefficient; and applying the sum of said first and second currents to a first resistive means and resistance of which being chosen to produce a required level shift.
Claim 13
Independent Claim
86 words
A method for level shifting a voltage, the amplitude of the level shift and the temperature coefficient thereof being independently controllable, comprising: generating a first current having a positive temperature coefficient; generating a second current having a negative temperature coefficient; varying the magnitude of said first and second currents to achieve a net negative, zero, or positive temperature coefficient; and applying the sum of said first and second currents to a first resistive means and resistance of which being chosen to produce a required level shift.
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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) | 1987-07-17 | 1988-01-16 | 1988-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-17 | 1992-01-16 | 1992-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-17 | 1996-01-16 | 1996-07-17 | $7700.00 | Window Closed / Lapsed |