US4021684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Push-pull power amplifier
Assignee: General Dynamics Government Systems Corp
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Filing: 1975-10-14
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Granted: 1977-05-03
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Expires: 1995-10-14
Abstract
Abstract Symmetrical push-pull power amplifier employing a pair of complementary output transistors having their collectors connected to an output terminal. The output transistors are each driven by an associated input transistor of the opposite conductivity type. Feedback diodes are coupled between the collector of each output transistor and the input of the input transistor associated with the other output transistor. A feedback diode is forward biased while the output transistor to which it is coupled is conducting, thus biasing to nonconduction the input transistor to which it is coupled. Therefore, when the polarity of the input signal to the input transistors changes, the output transistor that is off is not turned on until the output transistor that is on has dissipated the charge stored therein and is not conducting.
Inventors
- 👤 Frank G. Macey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:59
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
596 words
A push-pull amplifier circuit comprising an input terminal for receiving an input signal; an output terminal; first transistor means having its input coupled to said input terminal and its output coupled to said output terminal; said first transistor means including a first output transistor of one conductivity type having its collector connected directly to said output terminal and its emitter connected to a voltage source of one polarity, and a first input transistor of the opposite conductivity type having its base coupled to the input terminal and its collector coupled to the base of the first output transistor; said first transistor means being biased to conduction when the voltage at its input is of one polarity and being biased to nonconduction when the voltage at its input is of the opposite polarity; second transistor means having its input coupled to said input terminal and its output coupled to said output terminal; said second transistor means including a second output transistor of the opposite conductivity type having its collector connected directly to said output terminal and its emitter connected to a voltage source of the opposite polarity, and a second input transistor of the one conductivity type having its base coupled to the input terminal and its collector coupled to the base of the second output transistor; said second transistor means being biased to conduction when the voltage at its input is of said opposite polarity and being biased to nonconduction when the voltage at its input is of said one polarity; and feedback means including a first diode having a first terminal connected to the base of said second input transistor and having a second terminal, a second diode having a first terminal connected to the base of said first input transistor and having a second terminal connected to the second terminal of said first diode, and a resistance connected between the second terminals of said first and second diodes and said output terminal, said first diode being connected between said output terminal and the base of said second input transistor so as to be forward biased when the first output transistor is conducting, and said second diode being connected between said output terminal and the base of said first input transistor so as to be forward biased when the second output transistor is conducting; said feedback means being operable when the first transistor means is conducting to produce a voltage of the one polarity at the input of the second transistor means and being operable when the second transistor means is conducting to produce a voltage of the opposite polarity at the input of the first transistor means; said first transistor means being biased to conduction by the presence of a signal of the one polarity at the input terminal unless the feedback means is producing a voltage of the opposite polarity at the input of the first transistor means; and said second transistor means being biased to conduction by the presence of a signal of the opposite polarity at the input terminal unless the feedback means is producing a voltage of the one polarity at the input of the second transistor means; whereby when the input signal present at the input terminal changes from the one polarity to the opposite polarity said second transistor means is not biased to conduction until conduction terminates in the first transistor means, and when the input signal present at the input terminal changes from the opposite polarity to the one polarity said first transistor means is not biased to conduction until conduction terminates in the second transistor means.
Claim 2
Dependent Claim
596 words
A push-pull amplifier circuit comprising an input terminal for receiving an input signal; an output terminal; first transistor means having its input coupled to said input terminal and its output coupled to said output terminal; said first transistor means including a first output transistor of one conductivity type having its collector connected directly to said output terminal and its emitter connected to a voltage source of one polarity, and a first input transistor of the opposite conductivity type having its base coupled to the input terminal and its collector coupled to the base of the first output transistor; said first transistor means being biased to conduction when the voltage at its input is of one polarity and being biased to nonconduction when the voltage at its input is of the opposite polarity; second transistor means having its input coupled to said input terminal and its output coupled to said output terminal; said second transistor means including a second output transistor of the opposite conductivity type having its collector connected directly to said output terminal and its emitter connected to a voltage source of the opposite polarity, and a second input transistor of the one conductivity type having its base coupled to the input terminal and its collector coupled to the base of the second output transistor; said second transistor means being biased to conduction when the voltage at its input is of said opposite polarity and being biased to nonconduction when the voltage at its input is of said one polarity; and feedback means including a first diode having a first terminal connected to the base of said second input transistor and having a second terminal, a second diode having a first terminal connected to the base of said first input transistor and having a second terminal connected to the second terminal of said first diode, and a resistance connected between the second terminals of said first and second diodes and said output terminal, said first diode being connected between said output terminal and the base of said second input transistor so as to be forward biased when the first output transistor is conducting, and said second diode being connected between said output terminal and the base of said first input transistor so as to be forward biased when the second output transistor is conducting; said feedback means being operable when the first transistor means is conducting to produce a voltage of the one polarity at the input of the second transistor means and being operable when the second transistor means is conducting to produce a voltage of the opposite polarity at the input of the first transistor means; said first transistor means being biased to conduction by the presence of a signal of the one polarity at the input terminal unless the feedback means is producing a voltage of the opposite polarity at the input of the first transistor means; and said second transistor means being biased to conduction by the presence of a signal of the opposite polarity at the input terminal unless the feedback means is producing a voltage of the one polarity at the input of the second transistor means; whereby when the input signal present at the input terminal changes from the one polarity to the opposite polarity said second transistor means is not biased to conduction until conduction terminates in the first transistor means, and when the input signal present at the input terminal changes from the opposite polarity to the one polarity said first transistor means is not biased to conduction until conduction terminates in the second transistor means.
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) | 1980-05-02 | 1980-11-01 | 1981-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-02 | 1984-11-01 | 1985-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-02 | 1988-11-01 | 1989-05-03 | $7700.00 | Window Closed / Lapsed |