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US4600897A
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Voltage-controlled oscillator of emitter-coupled astable multivibrator type
Assignee: Toshiba Corp
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Filing: 1984-10-17
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Granted: 1986-07-15
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Expires: 2004-10-17
Abstract
Abstract A resistor, together with a charging capacitor, is connected in series between the emitters of transistors to constitute an emitter-coupled astable multivibrator to be used with a voltage-controlled oscillator. The resistance of the resistor is given by: R.sub.a =(τ.sub.d1 +τ.sub.d2)/2C.sub.a where C a is capacitance of the capacitor and (τ d1 +τ d2 ) is a delay time during one period of oscillation, as determined by the circuit elements.
Inventors
- 👤 Takashi Koga
- 👤 Hisakazu Hitomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:09
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/28; H03K3/281; H03K3/282; H03K3/2821
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
179 words
A voltage-controlled oscillator of the emitter-coupled astable multivibrator type comprising: a first transistor; a second transistor; a series circuit connected between the emitters of the first and second transistors and including at least a capacitor and an impedance element which exhibits an imaginary part for an operating frequency range of said voltage-controlled oscillator being negligible with respect to a real part, the real part consisting of a resistive value Ra which is so selected as to satisfy Ra=(τd1+τd2)/2Ca where Ca is the capacitance of said capacitor and (τd1+τd2) is a delay time during one oscillation period of the voltage controlled oscillator; first and second loads connected respectively to the collectors of said first and second transistors; feedback means connected between the collector of said first transistor and the base of said second transistor, and connected between the collector of said second transistor and the base of said first transistor; first and second current sources respectively connected to the emitters of said first and second transistors; and a control voltage source commonly connected to said first and second current sources.
Claim 2
Dependent Claim
179 words
A voltage-controlled oscillator of the emitter-coupled astable multivibrator type comprising: a first transistor; a second transistor; a series circuit connected between the emitters of the first and second transistors and including at least a capacitor and an impedance element which exhibits an imaginary part for an operating frequency range of said voltage-controlled oscillator being negligible with respect to a real part, the real part consisting of a resistive value Ra which is so selected as to satisfy Ra=(τd1+τd2)/2Ca where Ca is the capacitance of said capacitor and (τd1+τd2) is a delay time during one oscillation period of the voltage controlled oscillator; first and second loads connected respectively to the collectors of said first and second transistors; feedback means connected between the collector of said first transistor and the base of said second transistor, and connected between the collector of said second transistor and the base of said first transistor; first and second current sources respectively connected to the emitters of said first and second transistors; and a control voltage source commonly connected to said first and second current sources.
Claim 3
Dependent Claim
16 words
The voltage-controlled oscillator according to claim 1, in which said impedance elements is a single resistor.
Claim 4
Dependent Claim
51 words
The voltage-controlled oscillator according to claim 2, in which the resistance of said resistor is substantially equal to a value obtained when the sum of delay times caused by circuit elements during one period of the output signal of said voltage-controlled oscillator is divided by twice the capacitance of said capacitor.
Claim 5
Dependent Claim
21 words
The voltage-controlled oscillator according to claim 1, in which said impedance element is a couple of resistors having substantially equal resistances.
Claim 6
Dependent Claim
49 words
The voltage-controlled oscillator according to claim 4, in which said two resistors are respectively connected at one end to the emitters of said first and second transistors and at the other end to a pair of external pins, and said capacitor is connected between the pair of said pins.
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) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |