Patent US3701843A successfully refreshed from Google Patents.
US3701843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Matrix amplifier network with novel d-c set-up arrangement
Assignee: Zenith Electronics LLC
•
Filing: 1970-10-05
•
Granted: 1972-10-31
•
Expires: 1990-10-05
Abstract
Abstract A matrix amplifier network, preferably of a monolithic configuration, having three transistorized differential amplifiers and a common bias arrangement to maintain conduction at the same current level. Means are included to operate the differential amplifiers in push-pull fashion to develop the desired primary color control signals. The matrix amplifier network further includes a novel set-up arrangement incorporating respective voltage dividers interconnected in a manner to develop a d-c control potential for establishing and maintaining reference black level notwithstanding variations in the d-c output levels of the associated chroma demodulators as frequently encountered in integrated circuit arrangements between unit-tounit, or as may otherwise result from receiver power supply or line voltage fluctuations.
Inventors
- 👤 Charles F Hepner
- 👤 George J Tzakis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:40
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/67
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
273 words
A matrix amplifier network for developing push-pull color control signals from derived luminance and three color-difference signals representing red, blue and green color fields, and for establishing and maintaining d-c parameters defining reference black level, said amplifier network comprising in combination: three differential amplifiers each including a high impedance component and a pair of transistors each with collector, base and emitter electrodes, arranged in a Y-type configuration, with said high impedance component included in the collectoremitter paths of both of said transistor devices; common bias means for establishing substantially the same current flow in said high impedance component of each of said amplifiers; means for applying said luminance signal to said base electrodes of one of said pair of transistor devices in each of said amplifiers, and for applying said color-difference signals to the other of said pair of transistor devices of said amplifiers, respectively, the polarities of said applied signals being related to develop at said collectors of said pair of transistor devices of said amplifiers push-pull control signals representing the three color fields of the image being translated; matrix circuit means for developing a substantially d-c control voltage substantially free of color-difference signal information from respective portions of said applied colordifference signals; and means for utilizing said derived control voltage to maintain a substantially constant differential in applied signal voltages as between said base electrodes of each of said transistors comprising said transistor pairs and, in turn, substantially the same output voltage at said associated collector electrodes thereof notwithstanding variations in the applied signal levels at the base electrodes of each of said other transistors in each of said transistor pairs.
Claim 2
Dependent Claim
273 words
A matrix amplifier network for developing push-pull color control signals from derived luminance and three color-difference signals representing red, blue and green color fields, and for establishing and maintaining d-c parameters defining reference black level, said amplifier network comprising in combination: three differential amplifiers each including a high impedance component and a pair of transistors each with collector, base and emitter electrodes, arranged in a Y-type configuration, with said high impedance component included in the collectoremitter paths of both of said transistor devices; common bias means for establishing substantially the same current flow in said high impedance component of each of said amplifiers; means for applying said luminance signal to said base electrodes of one of said pair of transistor devices in each of said amplifiers, and for applying said color-difference signals to the other of said pair of transistor devices of said amplifiers, respectively, the polarities of said applied signals being related to develop at said collectors of said pair of transistor devices of said amplifiers push-pull control signals representing the three color fields of the image being translated; matrix circuit means for developing a substantially d-c control voltage substantially free of color-difference signal information from respective portions of said applied colordifference signals; and means for utilizing said derived control voltage to maintain a substantially constant differential in applied signal voltages as between said base electrodes of each of said transistors comprising said transistor pairs and, in turn, substantially the same output voltage at said associated collector electrodes thereof notwithstanding variations in the applied signal levels at the base electrodes of each of said other transistors in each of said transistor pairs.
Claim 3
Dependent Claim
105 words
A matrix amplifier network in accordance with claim 1 wherein said matrix circuit means include respective voltage divider means in the circuitry of each of said differential amplifiers, and a constant current source, said voltage divider means each including a resistance of a selected value connected between a respective base electrode of each of said other transistors of said transistor pairs and said common junction point, said constant current source including an additional transistor device having a base electrode coupled to said common bias means, a collector electrode coupled to said common junction point and an emittEr electrode returned to a plane of reference potential.
Claim 4
Dependent Claim
98 words
A matrix amplifier network in accordance with claim 1 wherein said matrix circuit means includes respective voltage divider means in the circuitry of each of said differential amplifiers, said voltage means each including a first resistance of a selected value connected between a respective base electrode of each of said other transistors of said transistor pairs and said common junction point, and a second resistance connected between said respective base electrodes and a plane of reference potential, said matrix circuit means further including additional resistance means connected between said common junction point and said plane of reference potential.
Claim 5
Dependent Claim
55 words
A matrix amplifier network in accordance with claim 2 wherein said resistances forming said respective voltage divider means include circuit values whereby the portions of color-difference signal information coupled therethrough and applied to said common junction point are substantially of equal magnitudes which when combined forms said control voltage essentially free of color-difference signal information.
Claim 6
Dependent Claim
117 words
A matrix amplifier network in accordance with claim 2 wherein the resistance connected between said base electrode of said other transistor of the transistor pair forming the differential amplifier for developing red push-pull color control signals is of a given resistance value, the resistance connected between the base electrode of said other transistor of the transistor pair forming the differential amplifier for developing blue push-pull color control signals is of a value approximately twice that of said given resistance, and the resistance connected between the base electrode of said other transistor of the transistor pair forming the differential amplifier for developing green push-pull color control signals is between one-third and one-fourth that of said given resistance value.
Claim 7
Dependent Claim
67 words
A matrix amplifier network in accordance with claim 1 wherein said means for applying said luminance signal to said differential amplifiers comprise three potentiometers, the body portions of said potentiometers being connected in parallel and the movable contact arms being selectively connected to said base electrodes of said one transistors in respective ones of said transistor pairs, said contact arms being selectively adjustable for low-level tracking action.
Claim 8
Dependent Claim
36 words
A matrix amplifier network in accordance with claim 1 and further including means comprising a trio of potentiometers interposed as voltage dividers in respective ones of said differential amplifier output circuits for providing high-level tracking action.
Claim 9
Dependent Claim
29 words
A matrix amplifier network in accordance with claim 1 wherein said high impedance component comprises the collector-emitter path of an additional transistor device having base, collector and emitter electrodes.
Claim 10
Dependent Claim
41 words
A matrix amplifier network in accordance with claim 1 which is constructed in a monolithic circuit configuration and in which said means for deriving said push-pull color control signals comprise a pair of output connections in each of said differential amplifiers.
Claim 11
Dependent Claim
56 words
A matrix amplifier network in accordance with claim 1 which further comprises means for applying to at least one transistor in each of said transistor pairs forming said differential amplifiers a periodically recurring retrace signal of such polarity as to introduce retrace blanking components into said push-pull color control signals for blanking action during retrace intervals.
Claim 12
Dependent Claim
124 words
In a color television receiver having a plurality of demodulators for deriving color-difference signals at respective outputs thereof representative of three color fields of a televised image, a matrix circuit arrangement for neutralizing the effect of shifts in the d-c operating levels of such demodulators, including in combination: a reference terminal; voltage divider means interconnecting each of said demodulator outputs and said reference terminal for combiNing portions of said color-difference signals to form on said reference terminal a control voltage in which the color-difference information effectively cancels and only a substantially d-c component remains, said d-c control voltage being representative of variations in the d-c operating levels of said demodulators; and means connected to said reference terminal for utilizing said derived d-c control voltage.
Claim 13
Dependent Claim
124 words
In a color television receiver having a plurality of demodulators for deriving color-difference signals at respective outputs thereof representative of three color fields of a televised image, a matrix circuit arrangement for neutralizing the effect of shifts in the d-c operating levels of such demodulators, including in combination: a reference terminal; voltage divider means interconnecting each of said demodulator outputs and said reference terminal for combiNing portions of said color-difference signals to form on said reference terminal a control voltage in which the color-difference information effectively cancels and only a substantially d-c component remains, said d-c control voltage being representative of variations in the d-c operating levels of said demodulators; and means connected to said reference terminal for utilizing said derived d-c control voltage.
Claim 14
Dependent Claim
167 words
In a matrix amplifier network including a plurality of differential amplifiers, each having a pair of inputs and a pair of output circuits for developing push-pull control signals, a matrix circuit arrangement for maintaining substantially fixed output signal levels at said respective differential amplifier output circuits over a given range of input signal levels, said matrix circuit arrangement including in combination: a source of signal information coupled to a selected one of said inputs of each of said differential amplifiers; voltage divider means connected between each of said selected ones of said differential amplifier inputs for combining portions of said applied signal information to form a substantially d-c control voltage essentially free of signal information components; and means for applying said derived control voltage to said other input of each of said differential amplifiers whereby the voltage difference between said inputs of each of said differential amplifiers remains substantially constant notwithstanding variations in the signal levels as applied to said selected ones of said differential amplifier inputs.
Claim 15
Dependent Claim
167 words
In a matrix amplifier network including a plurality of differential amplifiers, each having a pair of inputs and a pair of output circuits for developing push-pull control signals, a matrix circuit arrangement for maintaining substantially fixed output signal levels at said respective differential amplifier output circuits over a given range of input signal levels, said matrix circuit arrangement including in combination: a source of signal information coupled to a selected one of said inputs of each of said differential amplifiers; voltage divider means connected between each of said selected ones of said differential amplifier inputs for combining portions of said applied signal information to form a substantially d-c control voltage essentially free of signal information components; and means for applying said derived control voltage to said other input of each of said differential amplifiers whereby the voltage difference between said inputs of each of said differential amplifiers remains substantially constant notwithstanding variations in the signal levels as applied to said selected ones of said differential amplifier inputs.
Claim 16
Dependent Claim
173 words
A matrix circuit arrangement for establishing and maintaining d-c set-up parameters in a color television receiver having a matrix amplifier network in monolithic form comprised of a plurality of differential amplifiers, each of which includes a pair of inputs and a pair of output circuits for developing push-pull color control signals, said matrix set-up circuit arrangement including in combination: a source of color-difference signal information coupled to a selected one of said inputs of each of said differential amplifiers; circuit means interconnecting each of said selected ones of said differential amplifier inputs and a common junction point for combining portions of said applied color-difference signal information to form a substantially d-c control voltage; and means for applying said d-c control voltage to said other input of each of said differential amplifiers whereby a substantially constant voltage difference is maintained between said inputs of each of said differential amplifiers notwithstanding changes within a given range in the signal levels of the color-difference information as applied to said selected ones of said differential amplifier inputs.
Claim 17
Dependent Claim
173 words
A matrix circuit arrangement for establishing and maintaining d-c set-up parameters in a color television receiver having a matrix amplifier network in monolithic form comprised of a plurality of differential amplifiers, each of which includes a pair of inputs and a pair of output circuits for developing push-pull color control signals, said matrix set-up circuit arrangement including in combination: a source of color-difference signal information coupled to a selected one of said inputs of each of said differential amplifiers; circuit means interconnecting each of said selected ones of said differential amplifier inputs and a common junction point for combining portions of said applied color-difference signal information to form a substantially d-c control voltage; and means for applying said d-c control voltage to said other input of each of said differential amplifiers whereby a substantially constant voltage difference is maintained between said inputs of each of said differential amplifiers notwithstanding changes within a given range in the signal levels of the color-difference information as applied to said selected ones of said differential amplifier inputs.
References Cited (Backward Citations)
US3180928A
Cited
US3506776A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-31 | 1976-05-01 | 1976-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-31 | 1980-05-01 | 1980-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-31 | 1984-05-01 | 1984-10-31 | $7700.00 | Window Closed / Lapsed |