US4007415A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant voltage generating circuit
Assignee: Nikon Corp
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Filing: 1975-12-19
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Granted: 1977-02-08
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Expires: 1995-12-19
Abstract
Abstract A constant voltage generating circuit comprises a pair of first and second input terminals to which power source voltage is applied over the two terminals, an operational amplifier having output terminals supplying the constant output of the constant voltage generating circuit and two input terminals, a first resistor connected between the first input and one input of the amplifier, a second resistor connected between the first input terminal and the other input terminal of the amplifier, and a pair of logarithmic conversion diodes generating voltage which is logarithmically proportional to current flowing in itself. The circuit has an excellent stable output and a simple construction as well as has little wasted current and produces a constant voltage proportional to absolute temperature.
Inventors
- 👤 Kenji Toyoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:48
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/01; G01K7/02; G01K7/021; G05; G05F; G05F1/00; G05F1/10; G05F1/46; G05F1/56; G05F1/565; G05F1/567
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
156 words
In a constant voltage generating circuit which converts power source voltage to a constant voltage, the improvement comprising: a. a pair of first and second input terminals, to which power source voltage is applied b. an operational amplifier (OP hereafter) having an output terminal supplying the constant output of the constant voltage generating circuit and two input terminals; c. a first resistor element connected between the first input terminal and one input terminal of OP; d. a second resistor element connected between the first input terminal and the other input terminal of OP; and e. a pair of first and second logarithmic conversion elements generating voltage which is logarithmically proportional to current flowing in itself, the first logarithmic conversion element being connected between the first input terminal of OP and output terminal of OP and the second logarithmic conversion element being connected between the other input terminal and second input terminal of constant voltage generating circuit.
Claim 2
Dependent Claim
156 words
In a constant voltage generating circuit which converts power source voltage to a constant voltage, the improvement comprising: a. a pair of first and second input terminals, to which power source voltage is applied b. an operational amplifier (OP hereafter) having an output terminal supplying the constant output of the constant voltage generating circuit and two input terminals; c. a first resistor element connected between the first input terminal and one input terminal of OP; d. a second resistor element connected between the first input terminal and the other input terminal of OP; and e. a pair of first and second logarithmic conversion elements generating voltage which is logarithmically proportional to current flowing in itself, the first logarithmic conversion element being connected between the first input terminal of OP and output terminal of OP and the second logarithmic conversion element being connected between the other input terminal and second input terminal of constant voltage generating circuit.
Claim 3
Dependent Claim
35 words
A circuit according to claim 1, wherein each of the voltages of the first and second logarithmic conversion elements is proportional to absolute temperature to enable the constant voltage to be proportional to absolute temperature.
Claim 4
Dependent Claim
16 words
A circuit according to claim 2, wherein the first and second logarithmic conversion element are diodes.
Claim 5
Dependent Claim
21 words
A circuit according to claim 2, wherein the first logarithmic conversion element is transistor and the second conversion element is diode.
Claim 6
Dependent Claim
51 words
A circuit according to claim 1, further comprising a third resistor connected between the first logarithmic conversion element and the output terminal of OP and a fourth resistor connected between either the first or second input terminals, and the connecting point of the first logarithmic conversion element and the third resistor.
Claim 7
Dependent Claim
65 words
A circuit according to claim 1, further comprising a transistor having a control electrode connected to the output terminal of said operational amplifier and two main current carrying electrodes of which one is connected to said first logarithmic conversion element and of which the other feeds constant current, and a resistor connected between said one electrode and one of said first and second input terminals.
Claim 8
Dependent Claim
34 words
A circuit according to claim 6, further comprising a further resistor connected between the other electrode and the other of said first and second input terminals for producing constant voltage across said further resistor.
References Cited (Backward Citations)
US3851241A
Cited
US3959717A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-08 | 1980-08-09 | 1981-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-08 | 1984-08-09 | 1985-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-08 | 1988-08-09 | 1989-02-08 | $7700.00 | Window Closed / Lapsed |