US4782309A
Expired / Lapsed
US
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Bilateral frequency adjustment of crystal oscillators
Assignee: United States Department of the Army
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Filing: 1987-06-26
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Granted: 1988-11-01
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Expires: 2007-06-26
Abstract
Abstract A crystal oscillator in a bridge circuit coupled to a differential amplifier. Coordinated adjustment of one or two arms of the bridge permits pulling of the crystal's operating frequency both above and below its series resonant frequency.
Inventors
- 👤 Albert Benjaminson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:59
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/38; H03B2200/00; H03B2200/0002; H03B2200/0012
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
125 words
An oscillator circuit comprising: a bridge circuit including a first pair of first and second connected arms, each having an impedance reactance means and a second pair of connected arms, the first arm of said second pair having a piezoelectric crystal connected in series with a capacitive reactance means, and the second arm of said second pair having a capacitive reactance means connected in series with a resistor; a differential amplifier having an inverting input and a non-inverting input, said non-inverting input being connected between said first pair of arms and said inverting input being connected between said second pair of arms, the output of said amplifier being connected between said second arm of said second pair and said second arm of said first pair.
Claim 2
Dependent Claim
125 words
An oscillator circuit comprising: a bridge circuit including a first pair of first and second connected arms, each having an impedance reactance means and a second pair of connected arms, the first arm of said second pair having a piezoelectric crystal connected in series with a capacitive reactance means, and the second arm of said second pair having a capacitive reactance means connected in series with a resistor; a differential amplifier having an inverting input and a non-inverting input, said non-inverting input being connected between said first pair of arms and said inverting input being connected between said second pair of arms, the output of said amplifier being connected between said second arm of said second pair and said second arm of said first pair.
Claim 3
Dependent Claim
12 words
The device of claim 1 wherein both said impedance means are capacitive.
Claim 4
Dependent Claim
39 words
The device of claim 1 wherein said capacitive reactance means of said first arm of said second pair of arms and said capacitive reactance means of said second arm of said second pair of arms are adjustably connected together.
Claim 5
Dependent Claim
13 words
The device of claim 1 wherein said piezoelectric crystal is an AT cut.
Claim 6
Dependent Claim
13 words
The device of claim 1 wherein said piezoelectric crystal is an SC cut.
Claim 7
Dependent Claim
11 words
The device of claim 1 wherein said amplifier is a CA3001.
Claim 8
Dependent Claim
11 words
The device of claim 1 wherein said amplifier is a CA3040.
Claim 9
Dependent Claim
11 words
The device of claim 1 wherein said amplifier is a MC733.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-11-01 | 1992-05-02 | 1992-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-01 | 1996-05-02 | 1996-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-01 | 2000-05-02 | 2000-11-01 | $7700.00 | Window Closed / Lapsed |