US3587002A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage-controlled transistor multivibrator
Assignee: Ransomes Sims and Jeffries Ltd
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Filing: 1969-07-22
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Granted: 1971-06-22
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Expires: 1989-07-22
Abstract
Abstract A monostable or free-running transistor multivibrator is provided with semiconductor means for varying the period of conduction of one or both of the transistors forming the multivibrator in dependence upon a control voltage by varying the rate of discharge of the capacitor of the resistor-capacitor network whose time constant governs the period of conduction of the transistor. In one form of the invention the semiconductor means comprises an NPN transistor the collector-emitter path of which is in series with the capacitor of the associated resistor capacitor network, the control voltage being applied, directly or indirectly, to the base of the NPN transistor.
Inventors
- 👤 Christopher Robin Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:23
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/28; H03K3/281; H03K3/282; H03K3/2823; H03K3/284; H03K7/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
148 words
A multivibrator including first and second transistors at least one of which has connected therewith a resistor-capacitor network comprising a capacitor and resistor means through which, in operation, capacitor current flows during the period of conduction of the associated transistor, the rate of change of the charge on the capacitor determining the length of said period of conduction of the transistor, wherein there are provided semiconductor means (73 or 76) connected with the said resistorcapacitor network (65, 66 or 67, 68) and providing in parallel with said resistor means (65 or 67) a further path for the capacitor current, the semiconductor means being operable, in dependence upon a control voltage (A) applied thereto, to vary the rate of the change of charge on said capacitor during the period of conduction of the associated transistor thereby to vary the length of said period of conduction of the associated transistor.
Claim 2
Dependent Claim
148 words
A multivibrator including first and second transistors at least one of which has connected therewith a resistor-capacitor network comprising a capacitor and resistor means through which, in operation, capacitor current flows during the period of conduction of the associated transistor, the rate of change of the charge on the capacitor determining the length of said period of conduction of the transistor, wherein there are provided semiconductor means (73 or 76) connected with the said resistorcapacitor network (65, 66 or 67, 68) and providing in parallel with said resistor means (65 or 67) a further path for the capacitor current, the semiconductor means being operable, in dependence upon a control voltage (A) applied thereto, to vary the rate of the change of charge on said capacitor during the period of conduction of the associated transistor thereby to vary the length of said period of conduction of the associated transistor.
Claim 3
Dependent Claim
126 words
A multivibrator as claimed in claim 1 and of the free-running kind having first and second resistor-capacitor networks connected respectively with the first and second transistors and each comprising a capacitor and resistor means, wherein there are provided first and second semiconductor means (73 and 76) connected respectively with the first and second resistor-capacitor networks (65, 66 and 67, 68), each semiconductor means providing, in parallel with the resistor means of the associated resistor-capacitor network, a further capacitor path, and each being operable, in dependence upon a control voltage (A) applied thereto, to vary the rate of change of the charge on the capacitor (66 or 68) of the associated resistor-capacitor network, whereby the period of conduction of the associated transistor (61 or 62) is varied.
Claim 4
Dependent Claim
99 words
A multivibrator as claimed in claim 2, wherein the first and second semiconductor means (73 and 76) are operable in dependence upon the same control voltage, the first semiconductor means (73) being rendered increasingly heavily conducting upon rise in the control voltage thereby to increase the rate of change of charge on the capacitor (66) of the first resistor-capacitor network (65, 66), while the second semiconductor means (76) is Rendered less heavily conducting upon rise in the control voltage thereby to decrease the rate of change of charge on the capacitor (68) of the second resistor-capacitor network (67, 68).
Claim 5
Dependent Claim
70 words
A multivibrator as claimed in claim 1, wherein further control means are provided including a transistor (85) responsive to a further control voltage (B), the output of the transistor being used to operate one of the semiconductor means (76) to vary the rate of change of charge on the capacitor (68) of the associated resistor-capacitor network (67, 68) when the magnitude of the further control voltage exceeds a predetermined value.
Claim 6
Dependent Claim
44 words
A multivibrator as claimed in claim 4, wherein the transistor (85) responsive to the further control voltage is temperature compensated by the provision of a diode (86) the voltage across which varies in a similar manner to the base-emitter voltage of the transistor (85).
Claim 7
Dependent Claim
17 words
A multivibrator as claimed in claim 1 wherein the semiconductor means (73 or 76) comprises transistor means.
Claim 8
Dependent Claim
59 words
A multivibrator as claimed in claim 6 wherein the transistor means (73 or 76) comprises an N-P-N transistor the collector-emitter path of which is connected in series with the capacitor (66 or 68) of the associated resistor-capacitor network (65, 66 or 67, 68), the base-emitter bias voltage of the said N-P-N transistor being dependent on the control voltage (A).
Claim 9
Dependent Claim
41 words
A multivibrator as claimed in claim 7, wherein the control voltage is applied to the base of the said N-P-N transistor of the transistor means (73), so that a rise in the control voltage causes the transistor to conduct more heavily.
Claim 10
Dependent Claim
95 words
A multivibrator as claimed in claim 7, in which the control voltage is used to control the collector current of a P-N-P transistor and the base of the said N-P-N transistor (76) of the transistor means is connected to the junction of the collector of the P-N-P transistor and a resistor (82) in series with the collector-emitter path of the P-N-P transistor so that a rise in the control voltage causes a decrease in the potential of the base of the said N-P-N transistor (76) of the transistor means to render it less heavily conducting.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |