US3909738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amplifier device
Assignee: Hitachi Ltd
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Filing: 1973-07-26
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Granted: 1975-09-30
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Expires: 1993-07-26
Abstract
Abstract An amplifier device which dispenses with the normally required coupling capacitor between a band amplifier circuit and a color demodulator circuit, the band amplifier being used in the color restoring and color synchronizing system of a color television system. The amplifier device comprises a current source providing a constant current I0, a first circuit to divide the constant current I0 into two currents I1 and I2 and to control the current division ratio, a second circuit which includes a differential amplifier having the current I1 as its constant-current source and to which an input signal is supplied, and a third circuit which has the current I2 as its constant-current source and which has two current paths for dividing the current I2 into two currents I5 and I6, one of the two current paths of the third circuit being connected to a corresponding one of the outputs of the second circuit.
Inventors
- 👤 Masayasu Niimi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:24
CPC Classifications
H; H03; H03G; H03G1/00; H03G1/0005; H03G1/0017; H03G1/0023; H04; H04N; H04N9/00; H04N9/64; H04N9/68
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
168 words
An amplifier device comprising a constant current source providing a constant first current, a first differential amplifier means for dividing said constant first current into second and third currents in accordance with a controllable current division ratio, a second differential amplifier means connected to said first differential amplifier means to receive said second current as its constant-current source and having one input supplied with an input signal, a third differential amplifier means connected to said first differential amplifier means to receive said third current as its constant-current source and having two current paths for dividing said third current into respective fourth and fifth currents, one of said two current paths of said third differential amplifier means being connected to one of the outputs of said second differential amplifier means, and the other input of said second differential amplifier means being connected to one of the inputs of said third differential amplifier means, and constant bias means connected to both of said inputs of said third differential amplifier means.
Claim 2
Dependent Claim
168 words
An amplifier device comprising a constant current source providing a constant first current, a first differential amplifier means for dividing said constant first current into second and third currents in accordance with a controllable current division ratio, a second differential amplifier means connected to said first differential amplifier means to receive said second current as its constant-current source and having one input supplied with an input signal, a third differential amplifier means connected to said first differential amplifier means to receive said third current as its constant-current source and having two current paths for dividing said third current into respective fourth and fifth currents, one of said two current paths of said third differential amplifier means being connected to one of the outputs of said second differential amplifier means, and the other input of said second differential amplifier means being connected to one of the inputs of said third differential amplifier means, and constant bias means connected to both of said inputs of said third differential amplifier means.
Claim 3
Dependent Claim
34 words
An amplifier device as defined in claim 1, wherein said first differential amplifier means includes a transistor differential amplifier having its emitter circuit connected to said constant current source providing said constant first current.
Claim 4
Dependent Claim
52 words
An amplifier device as defined in claim 2, wherein said transistor differential amplifier comprises first and second transistors having their emitters connected together to said constant current source providing said constant first current, and a third transistor having its collector and emitter connected to the collector and emitter of said second transistor.
Claim 5
Dependent Claim
142 words
An amplifier device comprising a constant current source providing a first current, a first differential amplifier means connected to said constant current source for dividiNg said first current into second and third currents in accordance with a controllable current division ratio, a second differential amplifier means connected to said first differential amplifier means to receive said second current and having one input connected to a signal input terminal and the other input connected to a constant-voltage bias source, and current control means constituted by first and second resistors, each of said first and second resistors having one terminal connected in common to said first differential amplifier means for dividing said third current into fourth and fifth currents, and the other terminal of one of said first and second resistors being connected to one of the outputs of said second differential amplifier means.
Claim 6
Dependent Claim
142 words
An amplifier device comprising a constant current source providing a first current, a first differential amplifier means connected to said constant current source for dividiNg said first current into second and third currents in accordance with a controllable current division ratio, a second differential amplifier means connected to said first differential amplifier means to receive said second current and having one input connected to a signal input terminal and the other input connected to a constant-voltage bias source, and current control means constituted by first and second resistors, each of said first and second resistors having one terminal connected in common to said first differential amplifier means for dividing said third current into fourth and fifth currents, and the other terminal of one of said first and second resistors being connected to one of the outputs of said second differential amplifier means.
Claim 7
Dependent Claim
43 words
An amplifier device as defined in claim 4, wherein said first differential amplifier means comprises a transistor differential amplifier having its emitter circuit connected to said constant current source and one output connected to the emitter circuit of said second differential amplifier means.
Claim 8
Dependent Claim
32 words
An amplifier device as defined in claim 5, wherein said current paths of said current control means have one end connected together to the other output of said first differential amplifier means.
Claim 9
Dependent Claim
40 words
An amplifier device as defined in claim 6, wherein said first differential amplifier means comprises first and second transistors having their emitters connected together to said constant current source and a third transistor connected in parallel with said second transistor.
Claim 10
Dependent Claim
310 words
An amplifier device comprising: a current source providing a constant amplitude direct current; a first pair of amplifier means each having input, output and common electrodes, said common electrodes of said first pair of amplifier means being connected to said current source; means for supplying a gain control signal to said input electrodes of said first pair of amplifier means so as to control the ratio of direct currents which are divisions of said constant amplitude direct current and which flow through said first pair of amplifier means; a second pair of amplifier means each having input, output and common electrodes, said common electrodes of said second pair of amplifier means being connected to the output electrode of one of the amplifier means of said first pair of amplifier means; means for supplying a signal to be amplified to said input electrodes of said second pair of amplifier means; a terminal for supplying a power source; direct-current connecting means connected between said terminal and said output electrodes of said second pair of amplifier means, respectively, said direct-current connecting means including at least one load resistor; means coupled to said at least one load resistor for deriving an output signal; and a pair of direct-current supplying means each having output and common electrodes, said output electrodes of said pair of direct-current supplying means being connected to said output electrodes of said second pair of amplifier means, respectively, said common electrodes of said pair of direct-current supplying means being commonly connected to the output electrode of the other amplifier means of said first pair of amplifier means, said pair of direct-current supplying means dividing the direct current flowing through said other amplifier means of said first pair of amplifier means so that the respective direct-currents flowing through said direct-current connecting means become substantially constant irrespective of changes of said gain control signal.
Claim 11
Dependent Claim
310 words
An amplifier device comprising: a current source providing a constant amplitude direct current; a first pair of amplifier means each having input, output and common electrodes, said common electrodes of said first pair of amplifier means being connected to said current source; means for supplying a gain control signal to said input electrodes of said first pair of amplifier means so as to control the ratio of direct currents which are divisions of said constant amplitude direct current and which flow through said first pair of amplifier means; a second pair of amplifier means each having input, output and common electrodes, said common electrodes of said second pair of amplifier means being connected to the output electrode of one of the amplifier means of said first pair of amplifier means; means for supplying a signal to be amplified to said input electrodes of said second pair of amplifier means; a terminal for supplying a power source; direct-current connecting means connected between said terminal and said output electrodes of said second pair of amplifier means, respectively, said direct-current connecting means including at least one load resistor; means coupled to said at least one load resistor for deriving an output signal; and a pair of direct-current supplying means each having output and common electrodes, said output electrodes of said pair of direct-current supplying means being connected to said output electrodes of said second pair of amplifier means, respectively, said common electrodes of said pair of direct-current supplying means being commonly connected to the output electrode of the other amplifier means of said first pair of amplifier means, said pair of direct-current supplying means dividing the direct current flowing through said other amplifier means of said first pair of amplifier means so that the respective direct-currents flowing through said direct-current connecting means become substantially constant irrespective of changes of said gain control signal.
Claim 12
Dependent Claim
99 words
An amplifier device as defined in claim 8, wherein said pair of direct-current supplying means comprises a third pair of amplifier means each having input, output and common electrodes, said output electrodes of said third pair of amplifier means being connected to said output electrodes of said second pair of amplifier means, respectively, said common electrodes of said third pair of amplifier means being coMmonly connected to the output electrode of said other amplifier means of said first pair of amplifier means, and said input electrodes of said third pair of amplifier means being connected to constant bias means.
Claim 13
Dependent Claim
20 words
An amplifier device as defined in claim 8, wherein said pair of direct-current supplying means comprises a pair of resistors.
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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |