US4008440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplitude-limiter
Assignee: Iwasaki Tsushinki KK
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Filing: 1975-05-22
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Granted: 1977-02-15
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Expires: 1995-05-22
Abstract
Abstract An amplitude limiter, in which an input AC signal is applied to a first input of a differential amplifier and the output of the differential amplifier is positively fed back to a second input of the differential amplifier, so that an amplitude-limited output signal is derived from an output circuit coupled to the output terminal of the differential amplifier. A first diode is inserted in a line commonly connected to the feedback circuit and the output circuit of the differential amplifier to produce a positive periodic wave which is half-wave rectified from said input AC signal. A bias voltage set circuit is connected to the second input terminal of the differential amplifier to apply thereto a negative bias voltage to determine the negative limited level of the output of the differential amplifier. A second diode may be provided in the bias voltage set circuit in the direction of the bias current. The first rectifier element and the second rectifier element may have substantially the same temperature characteristics.
Inventors
- 👤 Shigeyuki Mizukoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:03
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/08; H03G; H03G11/00; H03G11/002
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
231 words
A limiter comprising: A differential amplifier having at least a first input terminal receptive of an input AC signal, a second input terminal, an output terminal for providing an output signal proportional to a difference between voltages respectively applied to said first input terminal and said second input terminal, a positive power source terminal receptive in use of a positive source voltage having a level which determines the positive level limit of the differential amplifier output signal, and a negative power source terminal; a feedback circuit connected between said output terminal of said differential amplifier and said second input terminal so that the output voltage derived from the output terminal of said differential amplifier is positively fed back to said second input terminal; an output circuit connected to said feedback circuit for deriving therefrom an amplitude-limited output signal; said feedback circuit including a rectifier element connected between said output terminal and said output circuit and having a polarity effective to pass positive portions of the differential amplifier output signal to said output circuit; and a bias voltage set circuit connected to said second input terminal for applying a negative bias voltage to said second input terminal and to limit conduction of said diode when the differential amplifier output signal is less than a certain value determined by the negative bias voltage, thereby to limit the negative level of the output signal.
Claim 2
Dependent Claim
231 words
A limiter comprising: A differential amplifier having at least a first input terminal receptive of an input AC signal, a second input terminal, an output terminal for providing an output signal proportional to a difference between voltages respectively applied to said first input terminal and said second input terminal, a positive power source terminal receptive in use of a positive source voltage having a level which determines the positive level limit of the differential amplifier output signal, and a negative power source terminal; a feedback circuit connected between said output terminal of said differential amplifier and said second input terminal so that the output voltage derived from the output terminal of said differential amplifier is positively fed back to said second input terminal; an output circuit connected to said feedback circuit for deriving therefrom an amplitude-limited output signal; said feedback circuit including a rectifier element connected between said output terminal and said output circuit and having a polarity effective to pass positive portions of the differential amplifier output signal to said output circuit; and a bias voltage set circuit connected to said second input terminal for applying a negative bias voltage to said second input terminal and to limit conduction of said diode when the differential amplifier output signal is less than a certain value determined by the negative bias voltage, thereby to limit the negative level of the output signal.
Claim 3
Dependent Claim
273 words
A limiter comprising: a differential amplifier having at least a first input terminal receptive of an input AC signal, a second input terminal, an output terminal for providing an output signal proportional to a difference between voltages respectively applied to said first input terminal and said second input terminal, a positive power source terminal receptive in use of a positive source voltage having a level which determines the positive level limit of the differential amplifier output signal, and a negative power source terminal; a feedback circuit connected between said output terminal of said differential amplifier and said second input terminal so that the output voltage derived from the output terminal of said differential amplifier is positively fed back to said second input terminal; an output circuit connected to said feedback circuit for deriving therefrom an amplitude output signal; said feedback circuit including a first rectifier element connected between said output terminal and said output circuit and having a polarity effective to pass positive portions of the differential amplifier output signal to said output circuit; and a bias voltage set circuit connected to said second input terminal for applying a negative bias voltage to said second input terminal and to limit conduction of said diode when the differential amplifier output signal is less than a certain value determined by the negative bias voltage thereby to limit the negative level of the output signal, and wherein said bias voltage set circuit includes a second rectifier element inserted in said bias voltage set circuit in the direction of the bias current of said bias voltage set circuit to provide a conductive path for the bias current.
Claim 4
Dependent Claim
273 words
A limiter comprising: a differential amplifier having at least a first input terminal receptive of an input AC signal, a second input terminal, an output terminal for providing an output signal proportional to a difference between voltages respectively applied to said first input terminal and said second input terminal, a positive power source terminal receptive in use of a positive source voltage having a level which determines the positive level limit of the differential amplifier output signal, and a negative power source terminal; a feedback circuit connected between said output terminal of said differential amplifier and said second input terminal so that the output voltage derived from the output terminal of said differential amplifier is positively fed back to said second input terminal; an output circuit connected to said feedback circuit for deriving therefrom an amplitude output signal; said feedback circuit including a first rectifier element connected between said output terminal and said output circuit and having a polarity effective to pass positive portions of the differential amplifier output signal to said output circuit; and a bias voltage set circuit connected to said second input terminal for applying a negative bias voltage to said second input terminal and to limit conduction of said diode when the differential amplifier output signal is less than a certain value determined by the negative bias voltage thereby to limit the negative level of the output signal, and wherein said bias voltage set circuit includes a second rectifier element inserted in said bias voltage set circuit in the direction of the bias current of said bias voltage set circuit to provide a conductive path for the bias current.
Claim 5
Dependent Claim
19 words
A limiter according to claim 2, wherein said first and second rectifier elements have substantially the same temperature characteristics.
References Cited (Backward Citations)
US3666970A
Cited
US3743950A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-15 | 1980-08-16 | 1981-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-15 | 1984-08-16 | 1985-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-15 | 1988-08-16 | 1989-02-15 | $7700.00 | Window Closed / Lapsed |