US4229666A
Expired / Lapsed
US
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Audio detector circuit
Assignee: Osram Sylvania Inc
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Filing: 1978-09-27
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Granted: 1980-10-21
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Expires: 1998-09-27
Abstract
Abstract A detector with independent TURNON and TURNOFF time constants. The TURNOFF time constant is connected between the output of an input transistor and the input of an output transistor. The TURNON time constant is coupled by a diode to the output of the output transistor and is connected to a Schmitt Trigger, ultimately driving an ON/OFF relay in a television receiver. Although the time constants are independently selectable, in a specific application of the invention the TURNON time constant may be chosen to be approximately twice the period of the detector input signal and about five times the TURNOFF time constant. Various configurations of series and parallel RC time constants are shown.
Inventors
- 👤 Zachariah H. Milburn, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:32
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/13
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
167 words
A detector circuit comprising: input means coupled to a source of input signals; first switching means having an input coupled to the input means; A TURNOFF time constant coupled to the output of the first switching means, said TURNOFF time constant for determining the time delay between the removal of an input signal and the corresponding change in detector output; second switching means having an input coupled to the output of the first switching means and to the TURNOFF time constant; a TURNON time constant, said TURNON time constant for determining the time delay between the reception of an input signal and the corresponding change in the detector output; and a unidirectional conducting device having a first electrode coupled to the output of the second switching means and a second electrode coupled to the TURNON time constant whereby the TURNON time constant is effectively disconnected from the second switching means during the reception of an input signal and effectively connected during the removal of an input signal.
Claim 2
Dependent Claim
167 words
A detector circuit comprising: input means coupled to a source of input signals; first switching means having an input coupled to the input means; A TURNOFF time constant coupled to the output of the first switching means, said TURNOFF time constant for determining the time delay between the removal of an input signal and the corresponding change in detector output; second switching means having an input coupled to the output of the first switching means and to the TURNOFF time constant; a TURNON time constant, said TURNON time constant for determining the time delay between the reception of an input signal and the corresponding change in the detector output; and a unidirectional conducting device having a first electrode coupled to the output of the second switching means and a second electrode coupled to the TURNON time constant whereby the TURNON time constant is effectively disconnected from the second switching means during the reception of an input signal and effectively connected during the removal of an input signal.
Claim 3
Dependent Claim
53 words
A detector circuit as defined in claim 1 wherein the TURNOFF time constant comprises a resistive branch coupled between the output of the first switching means and a first source of reference potential and a capacitive branch coupled between the output of the first switching device and a second source of reference potential.
Claim 4
Dependent Claim
38 words
A detector circuit as defined in claim 1 wherein the TURNOFF time constant comprises a resistive branch and a capacitive branch, each coupled between the output of the first switching means and a first source of reference potential.
Claim 5
Dependent Claim
55 words
A detector circuit as defined in claim 1 wherein the TURNON time constant comprises a capacitive branch coupled between the second electrode of the unidirectional conducting device and a first source of reference potential and a resistive branch coupled between the second electrode of the unidirectional conducting device and a second source of reference potential.
Claim 6
Dependent Claim
39 words
A detector circuit as defined in claim 1 wherein the TURNON time constant comprises a resistive branch and a capacitive branch, each coupled between the second electrode of the unidirectional conducting device and a second source of reference potential.
Claim 7
Dependent Claim
38 words
A detector circuit as defined in claim 2 wherein the TURNON time constant comprises a resistive and a capacitive branch, each coupled between the second electrode of the unidirectional conducting device and the second source of reference potential.
Claim 8
Dependent Claim
55 words
A detector circuit as defined in claim 3 wherein the TURNON time constant comprises a capacitive branch coupled between the second electrode of the unidirectional conducting device and the first source of reference potential and a resistive branch coupled between the second electrode of the unidirectional conducting device and a second source of reference potential.
Claim 9
Dependent Claim
38 words
A detector circuit as defined in claim 6 or claim 7 wherein the unidirectional conducting device is so arranged and constructed as to conduct current from the output of the second switching device into the TURNON time constant.
Claim 10
Dependent Claim
55 words
A detector circuit as defined in claim 3 wherein the TURNON time constant comprises a resistive branch coupled between the second electrode of the unidirectional conducting device and the first source of reference potential and a capacitive branch coupled between the second electrode of the unidirectional conducting device and a second source of reference potential.
Claim 11
Dependent Claim
35 words
A detector circuit as defined in claim 9 wherein the unidirectional conducting device is so arranged and constructed as to conduct current into the output of the second switching means from the TURNON time constant.
Claim 12
Dependent Claim
22 words
A detector circuit as defined in claim 1 wherein the TURNON time constant is at least five times the TURNOFF time constant.
Claim 13
Dependent Claim
24 words
A detector circuit as defined in claim 11 wherein the TURNOFF time constant is at least twice the period of the detector input signal.
Claim 14
Dependent Claim
100 words
A detector circuit comprising: a first transistor having an input coupled to a source of input signals; a second transistor having an input coupled to the output of the first transistor; a TURNOFF time constant connected to both the output of the first transistor and to the input of the second transistor, said TURNOFF time constant for determining the time delay between the removal of an input signal and the corresponding change in the detector output; a TURNON time constant for determining the time delay between the reception of an input signal and the corresponding change in the detector output;
Claim 15
Dependent Claim
100 words
A detector circuit comprising: a first transistor having an input coupled to a source of input signals; a second transistor having an input coupled to the output of the first transistor; a TURNOFF time constant connected to both the output of the first transistor and to the input of the second transistor, said TURNOFF time constant for determining the time delay between the removal of an input signal and the corresponding change in the detector output; a TURNON time constant for determining the time delay between the reception of an input signal and the corresponding change in the detector output;
Claim 16
Dependent Claim
148 words
a unidirectional conducting device connected between the output of the second transistor and the TURNON time constant said device for effectively disconnecting the second transistor from the TURNON time constant during the reception of an input signal and effectively connecting the second transistor from the TURNON time constant during the removal of an input signal; and a hysteresis-exhibiting pulse-shaper connected to the junction of the unidirectional conducting device and TURNON time constant, whereby the TURNON time constant determines the delay between the time at which an input signal is applied to the input of the first transistor and the time at which the pulse-shaper changes state in a first sense and the TURNOFF time constant determines the delay between the time at which the input signal is removed from the input of the first transistor and the time at which the pulse-shaper changes state in a second sense.
Claim 17
Dependent Claim
148 words
a unidirectional conducting device connected between the output of the second transistor and the TURNON time constant said device for effectively disconnecting the second transistor from the TURNON time constant during the reception of an input signal and effectively connecting the second transistor from the TURNON time constant during the removal of an input signal; and a hysteresis-exhibiting pulse-shaper connected to the junction of the unidirectional conducting device and TURNON time constant, whereby the TURNON time constant determines the delay between the time at which an input signal is applied to the input of the first transistor and the time at which the pulse-shaper changes state in a first sense and the TURNOFF time constant determines the delay between the time at which the input signal is removed from the input of the first transistor and the time at which the pulse-shaper changes state in a second sense.
Claim 18
Dependent Claim
77 words
A detector circuit as defined in claim 13 wherein the TURNOFF time constant comprises a resistor connected between a first potential voltage and the input of the second transistor and a capacitor connected to the resistor so that the first transistor is conducting during half-cycles of the input signal having one polarity and otherwise nonconducting and the second transistor is nonconducting during both half-cycles of the input signal but is conducting when the input signal is removed.
Claim 19
Dependent Claim
34 words
A detector circuit as defined in claim 14 wherein the TURNON time constant comprises a resistor connected between a second potential voltage and the unidirectional conducting device and a capacitor connected to the resistor.
Claim 20
Dependent Claim
59 words
A detector as defined in claim 15 wherein the capacitor of the TURNON time constant is also connected to the second potential voltage so that when the second transistor is conducting the capacitor is charged through the unidirectional conducting device and when the second transistor is nonconducting the capacitor is discharged through the resistor of the TURNON time constant.
Claim 21
Dependent Claim
59 words
A detector as defined in claim 15 wherein the capacitor of the TURNON time constant is connected also to the first potential voltage so that when the second transistor is conducting the capacitor is discharged through the unidirectional conducting device and when the second transistor is nonconducting the capacitor is charged through the resistor of the TURNON time constant.
Claim 22
Dependent Claim
77 words
A detector circuit as defined in claim 14 wherein the TURNON time constant comprises a resistor connected between the unidirectional conducting device and the first potential voltage and a capacitor connected between the unidirectional conducting device and a second potential voltage so that when the second transistor is conducting the capacitor is discharged through the unidirectional conducting device and when the second transistor is nonconducting the capacitor is charged through the resistor of the TURNON time constant.
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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) | 1983-10-21 | 1984-04-21 | 1984-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-21 | 1988-04-21 | 1988-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-21 | 1992-04-21 | 1992-10-21 | $7700.00 | Window Closed / Lapsed |