Patent US3996530A successfully refreshed from Google Patents.
US3996530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Butler oscillator
Assignee: International Business Machines Corp
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Filing: 1975-06-30
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Granted: 1976-12-07
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Expires: 1995-06-30
Abstract
Abstract An amplitude limiting amplifier followed by a filter network is interposed between the voltage amplification stage and the impedance matching stage in a Butler oscillator. This allows both the voltage amplification stage and the impedance matching stage to be operated in a linear mode at all times which assures that a piezoelectric crystal connected between the stages is connected in a relatively low, constant impedance path and is driven by a sinusoidal waveform, free of distortion, to assure maximum frequency stability.
Inventors
- 👤 Claude Herbert Feistel
- 👤 Philip Theodore Gianos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:01
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/36; H03B2200/00; H03B2200/0002; H03B2200/0004
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
97 words
In a Butler oscillator, the improvement comprising: an amplitude limiting differential amplifier having an input connected to an output of a voltage amplifier stage of said oscillator, said limiting amplifier having a first output connected in a feedback path of said oscillator to a filter, said filter being connected to an input of an impedance matching stage of said oscillator and said amplifier having a second output of a portion of said amplifier outside said feedback path, said second output being connected to a signal output terminal for providing a square wave output signal from said oscillator.
Claim 2
Dependent Claim
97 words
In a Butler oscillator, the improvement comprising: an amplitude limiting differential amplifier having an input connected to an output of a voltage amplifier stage of said oscillator, said limiting amplifier having a first output connected in a feedback path of said oscillator to a filter, said filter being connected to an input of an impedance matching stage of said oscillator and said amplifier having a second output of a portion of said amplifier outside said feedback path, said second output being connected to a signal output terminal for providing a square wave output signal from said oscillator.
Claim 3
Dependent Claim
46 words
The oscillator of claim 1 wherein said filter is a parallel resonant tank circuit having one terminal connected to an output of said differential amplifier and said input of said impedance matching stage and another terminal connecting through a substantially low alternating current impedance to ground.
Claim 4
Dependent Claim
31 words
The oscillator of claim 2 wherein a voltage attenuator is interposed in the connection path between said one terminal of said tank circuit and said input of said impedance matching stage.
Claim 5
Dependent Claim
42 words
The oscillator of claim 3 wherein said differential amplifier includes a first input connected to said output of said voltage amplifier stage and a second input connected to an output of another stage configured substantially the same as said voltage amplifier stage.
Claim 6
Dependent Claim
163 words
An oscillator circuit comprising: a voltage amplification stage having an input and an output; an amplitude limiting differential amplifier stage having a first output and having an input connected to said output of said voltage amplification stage, said first output and said input of said amplifier being connected in a feedback path of said oscillator; an impedance matching stage having an input and an output; a filter connecting said first output of said amplitude limiting stage and said input of said impedance matching stage, said filter being operative to provide a relatively pure, sinusoidal waveform to said input of said impedance matching stage; and a series of resonant circuit connecting said output of said impedance matching stage to said input of said voltage amplification stage; and said differential amplifier having a second output of a portion of said amplifier outside said feedback path, said second output being connected to a signal output terminal for providing a square wave output signal from said oscillator.
Claim 7
Dependent Claim
163 words
An oscillator circuit comprising: a voltage amplification stage having an input and an output; an amplitude limiting differential amplifier stage having a first output and having an input connected to said output of said voltage amplification stage, said first output and said input of said amplifier being connected in a feedback path of said oscillator; an impedance matching stage having an input and an output; a filter connecting said first output of said amplitude limiting stage and said input of said impedance matching stage, said filter being operative to provide a relatively pure, sinusoidal waveform to said input of said impedance matching stage; and a series of resonant circuit connecting said output of said impedance matching stage to said input of said voltage amplification stage; and said differential amplifier having a second output of a portion of said amplifier outside said feedback path, said second output being connected to a signal output terminal for providing a square wave output signal from said oscillator.
Claim 8
Dependent Claim
46 words
The oscillator of claim 5 wherein said filter is a parallel resonant tank circuit having one terminal connected to an output of said differential amplifier and said input of said impedance matching stage and another terminal connected through a substantially low alternating current impedance to ground.
Claim 9
Dependent Claim
31 words
The oscillator of claim 6 wherein a voltage attenuator is interposed in the connection path between said one terminal of said tank circuit and said input of said impedance matching stage.
Claim 10
Dependent Claim
42 words
The oscillator of claim 7 wherein said differential amplifier includes a first input connected to said output of said voltage amplifier stage and a second input connect to an output of another stage configured substantially the same as said voltage amplifier stage.
Claim 11
Dependent Claim
14 words
The oscillator of claim 8 wherein said series resonant circuit is a piezoelectric crystal.
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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) | 1979-12-07 | 1980-06-07 | 1980-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-07 | 1984-06-07 | 1984-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-07 | 1988-06-07 | 1988-12-07 | $7700.00 | Window Closed / Lapsed |