Patent US3737796A successfully refreshed from Google Patents.
US3737796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linearly controlled amplifier
Assignee: Robert Bosch Fernsehanlagen GmbH
•
Filing: 1971-12-07
•
Granted: 1973-06-05
•
Expires: 1991-12-07
Abstract
Abstract A linearly controlled amplifier has delay-free amplification control. The amplifier has a first cascode amplification stage for amplifying an alternating current signal which has a nonlinear gain control characteristic for amplifying the signal. A control voltage is supplied to the first amplification stage for controlling the gain of the latter. A second cascode amplification stage is connected to the control means for distorting the control signal applied to the first amplification stage. The second amplification stage comprises a DC amplifier and is provided with negative feedback for distorting the control voltage. The application of the thus predistorted control voltage to the first amplification stage results in a linear relationship between the control voltage and the gain of the first amplification stage. Each of the stages consist of the cascode amplifier has one input and two output transistors.
Inventors
- 👤 E Legler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:49
CPC Classifications
H; H03; H03G; H03G1/00; H03G1/0005; H03G1/0017; H03G1/0023
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
153 words
An amplifier having gain control, comprising in combination a first amplifying circuit and a dummy amplifying circuit, the two amplifying circuits having the same general circuit configuration, and each having a principal input for a signal to be amplified, a control input for a gain-control signal and an output, and each of said circuits being capable of producing at its output an amplified signal with a gain dependent upon the magnitude of a gain-control signal applied to its control input; means for transmitting a gain-control signal to the control inputs of both of said circuits; and negative feedback means connected between the output of said dummy circuit and said control inputs and operative for linearizing the dependence of the gain of said first cIrcuit upon the magnitude of said gaincontrol signal by applying to the control input of said first circuit a negative feedback signal dependent upon the output of said dummy circuit.
Claim 2
Dependent Claim
153 words
An amplifier having gain control, comprising in combination a first amplifying circuit and a dummy amplifying circuit, the two amplifying circuits having the same general circuit configuration, and each having a principal input for a signal to be amplified, a control input for a gain-control signal and an output, and each of said circuits being capable of producing at its output an amplified signal with a gain dependent upon the magnitude of a gain-control signal applied to its control input; means for transmitting a gain-control signal to the control inputs of both of said circuits; and negative feedback means connected between the output of said dummy circuit and said control inputs and operative for linearizing the dependence of the gain of said first cIrcuit upon the magnitude of said gaincontrol signal by applying to the control input of said first circuit a negative feedback signal dependent upon the output of said dummy circuit.
Claim 3
Dependent Claim
18 words
An amplifier as defined in claim 1, wherein each of said amplifying circuits is a cascode transistor circuit.
Claim 4
Dependent Claim
60 words
An amplifier as defined in claim 2, wherein each of said amplifying circuits includes one input transistor and two output transistors, the collector of said input transistor being connected to the emitters of said output transistors, with the base of said input transistor constituting said principal input and the base of one of said output transistors constituting said control input.
Claim 5
Dependent Claim
36 words
An amplifier as defined in claim 1, wherein said negative feedback means is furthermore operative for making the D.C. level at the output of said dummy circuit linearly dependent upon the magnitude of said gain-control signal.
Claim 6
Dependent Claim
40 words
An amplifier as defined in claim 3, wherein said negative feedback means is furthermore operative for making the magnitudes of D.C. collector currents of said output transistors of said dummy circuit linearly dependent upon the magnitude of said gain-control signal.
Claim 7
Dependent Claim
34 words
An amplifier as defined in claim 1, wherein said dummy circuit has an additional complementary output, and wherein said output of said first circuit is connected to said complementary output of said dummy circuit.
Claim 8
Dependent Claim
28 words
An amplifier as defined in claim 3, wherein the transistors of said two circuits are so biassed that the D.C. collector currents of both input transistors are equal.
Claim 9
Dependent Claim
103 words
An amplifier as defined in claim 3, wherein that transistor of said dummy circuit whose base constitutes the control input thereof furthermore has a collector constituting the output of said dummy circuit, and wherein said control inputs are connected to each other, and wherein said means for transmitting a gain-control signal includes a decoupling resistance having one end connected to said control inputs and having another end available for receipt of said gain-control signal, and wherein said negative feedback means includes a feedback resistor having one end connected to said control inputs and another end connected to said output of said dummy circuit.
Claim 10
Dependent Claim
206 words
An amplifier having gain control, comprising in combination a first amplifying circuit and a dummy amplifying circuit, the two amplifying circuits having the same general circuit configuration, and each having a principal input for a signal to be amplified, a control input for a gain control signal and an output, and each of said circuits being capable of producing at its output an amplified signal with a gain dependent upon the magnitude of a gain-control signal applied to its control input; means for transmitting a gain-control signal to the control inputs of both of said circuits; means for applying to the principal input of said first circuit an A.C. input signal to be amplified; means for applying to the principal input of said dummy circuit only a steady-value D.C. signal, so that the signal at the output of said dummy circuit will have substantially no A.C. component; and negative feedback means connected between the output of said dummy circuit and said control inputs and operative for linearizing the dependence of the gain of said first circuit upon the magnitude of said gain-control signal by applying to the control input of said first circuit a negative feedback signal dependent upon the output level of said dummy circuit.
Claim 11
Dependent Claim
206 words
An amplifier having gain control, comprising in combination a first amplifying circuit and a dummy amplifying circuit, the two amplifying circuits having the same general circuit configuration, and each having a principal input for a signal to be amplified, a control input for a gain control signal and an output, and each of said circuits being capable of producing at its output an amplified signal with a gain dependent upon the magnitude of a gain-control signal applied to its control input; means for transmitting a gain-control signal to the control inputs of both of said circuits; means for applying to the principal input of said first circuit an A.C. input signal to be amplified; means for applying to the principal input of said dummy circuit only a steady-value D.C. signal, so that the signal at the output of said dummy circuit will have substantially no A.C. component; and negative feedback means connected between the output of said dummy circuit and said control inputs and operative for linearizing the dependence of the gain of said first circuit upon the magnitude of said gain-control signal by applying to the control input of said first circuit a negative feedback signal dependent upon the output level of said dummy circuit.
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) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |