Patent US4068183A successfully refreshed from Google Patents.
US4068183A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistorized single ended push-pull amplifier having no cross-over distortion
Assignee: Sony Corp
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Filing: 1975-03-03
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Granted: 1978-01-10
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Expires: 1995-03-03
Abstract
Abstract An amplifier circuit comprising a single ended push-pull amplifying stage comprised of field effect transistors. A pre-amplifier stage formed of a differential amplifier is coupled to the single ended push-pull amplifying stage for supplying a signal thereto. The output terminals of the differential amplifier are connected to the respective gate electrodes of the field effect transistors included in the single ended push-pull amplifying stage, and load impedance means couple the differential amplifier output terminals to the source or drain electrodes of the field effect transistors. A variable current source is connected to the differential amplifier for controlling the current flowing through the differential amplifier as a function of variations in the operating voltage that is supplied to the load connected to the single ended push-pull amplifying stage. Variations in this operating voltage cause corresponding changes in the differential amplifier current to thereby change the bias level of the signal supplied by the differential amplifier to the single ended push-pull amplifying stage so as to maintain the idling currents of the field effect transistors at a substantially constant level, thus preventing the occurrence of cross-over distortion.
Inventors
- 👤 Hiroshi Horinaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:30
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/45376; H03F1/00; H03F1/30; H03F3/30; H03F3/3001; H03F3/3044
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
319 words
A transistor amplifier, comprising: source means for supplying an operating voltage; first and second field effect transistor means each having triode operating characteristics and each including gate, source and drain electrodes; means for applying said operating voltage across the drain and source electrodes of said first field effect transistor means through a load; means for applying said operating voltage across the drain and source electrodes of said second field effect transistor means through said load; driving means coupled to said first and second field effect transistor means and responsive to an input signal for controlling the alternate conduction of said first and second field effect transistor means, said driving means comprising a differential amplifier formed of differentially-connected transistors each having an input electrode and at least one output electrode, means for applying said input signal to said input electrodes of said differentially-connected transistors, a first load impedance for coupling the output electrode of one of said differentially-connected transistors to said first field effect transistor means to apply a first bias voltage to said first field effect transistor means and to apply a first drive signal to the gate electrode of said first field effect transistor means, and a second load impedance for coupling the output electrode of the other of said differentially-connected transistors to said second field effect transistor means to apply a second bias voltage to said second field effect transistor means and to apply a second drive signal to the gate electrode of said second field effect transistor means; and current control means connected to said differential amplifier for changing the current flowing through said differentially-connected transistors in accordance with changes in the operating voltage supplied by said source means to thereby change said first and second bias voltages applied to said first and second field effect transistor means such that the idling currents of said first and second field effect transistor means are maintained substantially constant.
Claim 2
Dependent Claim
319 words
A transistor amplifier, comprising: source means for supplying an operating voltage; first and second field effect transistor means each having triode operating characteristics and each including gate, source and drain electrodes; means for applying said operating voltage across the drain and source electrodes of said first field effect transistor means through a load; means for applying said operating voltage across the drain and source electrodes of said second field effect transistor means through said load; driving means coupled to said first and second field effect transistor means and responsive to an input signal for controlling the alternate conduction of said first and second field effect transistor means, said driving means comprising a differential amplifier formed of differentially-connected transistors each having an input electrode and at least one output electrode, means for applying said input signal to said input electrodes of said differentially-connected transistors, a first load impedance for coupling the output electrode of one of said differentially-connected transistors to said first field effect transistor means to apply a first bias voltage to said first field effect transistor means and to apply a first drive signal to the gate electrode of said first field effect transistor means, and a second load impedance for coupling the output electrode of the other of said differentially-connected transistors to said second field effect transistor means to apply a second bias voltage to said second field effect transistor means and to apply a second drive signal to the gate electrode of said second field effect transistor means; and current control means connected to said differential amplifier for changing the current flowing through said differentially-connected transistors in accordance with changes in the operating voltage supplied by said source means to thereby change said first and second bias voltages applied to said first and second field effect transistor means such that the idling currents of said first and second field effect transistor means are maintained substantially constant.
Claim 3
Dependent Claim
82 words
The transistor amplifier of claim 1 wherein said current control means comprises a controllable current source connected to said differential amplifier such that the currents flowing through said output electrodes of said differentially-connected transistors flow through said current source; and voltage detecting means connected to said source means to detect changes in said operating voltage, said voltage detecting means being coupled to said current source to vary the current flow therethrough as a function of said detected changes in said operating voltage.
Claim 4
Dependent Claim
39 words
The transistor amplifier of claim 2 wherein said controllable current source comprises a transistor having a control electrode and output electrodes, said output electrodes being connected in series with impedance means between said differential amplifier and a reference voltage.
Claim 5
Dependent Claim
46 words
The transistor amplifier of claim 3 wherein said voltage detecting means comprises means for deriving a voltage proportional to said operating voltage, said derived voltage including any changes in said operating voltage; and means for supplying said derived voltage to said control electrode of said transistor.
Claim 6
Dependent Claim
32 words
The transistor amplifier of claim 4 wherein said voltage deriving means comprises a voltage divider circuit connected to said source means and having an output terminal coupled to said transistor control electrode.
Claim 7
Dependent Claim
64 words
The transistor amplifier of claim 4 wherein said differential amplifier is comprised of differentially-connected field effect transistors having their respective gate electrodes supplied with said input signals, their respective source electrodes connected in common to said current source transistor and their respective drain electrodes coupled to respective ones of said first and second field effect transistor means by said first and second load impedances.
Claim 8
Dependent Claim
37 words
The transistor amplifier of claim 6 wherein the source electrode of said first field effect transistor means and the drain electrode of said second field effect transistor means are connected together and in common to said load.
Claim 9
Dependent Claim
114 words
The transistor amplifier of claim 7 wherein said first load impedance comprises first resistance means for coupling the drain electrode of one of said differentially-connected transistors to the source electrode of said first field effect transistor means, the gate electrode of said first field effect transistor means being connected through said first resistance means to the source electrode thereof; and wherein said second load impedance comprises second resistance means for coupling the drain electrode of the other of said differentially-connected transistors to the source electrode of said second field effect transistor means, the gate electrode of said second field effect transistor means being connected through said second resistance means to the source electrode thereof.
Claim 10
Dependent Claim
116 words
The transistor amplifier of claim 7 wherein said first load impedance comprises first resistance means for coupling the drain electrode of one of said differentially-connected transistors to the drain electrode of said first field effect transistor means, the gate electrode of said first field effect transistor means being connected through said first resistance means to the drain electrode thereof; and wherein said second load impedance means comprises second resistance means for coupling the drain electrode of the other of said differentially connected transistors to the drain electrode of said second field effect transistor means, the gate electrode of said second field effect transistor means being connected through said second resistance means to the drain electrode thereof.
Claim 11
Dependent Claim
93 words
The transistor amplifier of claim 9 wherein said first resistance means comprises a first pair of series-connected resistors defining a junction therebetween, and said first load impedance means further comprises a first capacitor for coupling said junction to the source electrode of said first field effect transistor means; and wherein said second resistance means comprises a second pair of series-connected resistors defining a second junction therebetween, and said second load impedance means further comprises a second capacitor for coupling said second junction to the source electrode of said second field effect transistor means.
Claim 12
Dependent Claim
24 words
The transistor amplifier of claim 7, further comprising a source of bias potential connected between said reference voltage and said operating voltage source means.
Claim 13
Dependent Claim
230 words
Am amplifier circuit, comprising: a single ended push-pull amplifying stage comprised of first and second field effect transistor means, the source electrode of one of said field effect transistor means being connected to the drain electrode of said other field effect transistor means to form a junction, a load connected to said junction, and means for supplying an operating voltage through said load to each of said field effect transistor means; a pre-amplifier stage for supplying a signal to said single ended push-pull amplifying stage, said pre-amplifier stage comprised of a differential amplifier formed of differentially-connected transistors to receive an input signal applied thereto and having a pair of output terminals connected to the respective gate electrodes of said first and second field effect transistor means, and first and second load impedance means for coupling the output terminals of said differentially-connected transistors to one of said source and drain electrodes of said first and second field effect transistor means, respectively; and a variable current source connected to said differentially-connected transistors for controlling the current flowing through said differentially-connected transistors as a function of variations in said operating voltage to thereby change the bias level of said signal supplied by said differential amplifier to said single ended push-pull amplifying stage so as to maintain the idling currents of said first and second field effect transistor means at a substantially constant level.
Claim 14
Dependent Claim
230 words
Am amplifier circuit, comprising: a single ended push-pull amplifying stage comprised of first and second field effect transistor means, the source electrode of one of said field effect transistor means being connected to the drain electrode of said other field effect transistor means to form a junction, a load connected to said junction, and means for supplying an operating voltage through said load to each of said field effect transistor means; a pre-amplifier stage for supplying a signal to said single ended push-pull amplifying stage, said pre-amplifier stage comprised of a differential amplifier formed of differentially-connected transistors to receive an input signal applied thereto and having a pair of output terminals connected to the respective gate electrodes of said first and second field effect transistor means, and first and second load impedance means for coupling the output terminals of said differentially-connected transistors to one of said source and drain electrodes of said first and second field effect transistor means, respectively; and a variable current source connected to said differentially-connected transistors for controlling the current flowing through said differentially-connected transistors as a function of variations in said operating voltage to thereby change the bias level of said signal supplied by said differential amplifier to said single ended push-pull amplifying stage so as to maintain the idling currents of said first and second field effect transistor means at a substantially constant level.
Claim 15
Dependent Claim
45 words
The amplifier circuit of claim 12 wherein said variable current source comprises a controllable transistor having its output electrodes connected with resistance means to form a series circuit, said series circuit being connected between the common-connected electrodes of said differentially-connected transistors and a reference potential.
Claim 16
Dependent Claim
38 words
The amplifying circuit of claim 13 wherein said variable current source further comprises voltage detecting means for detecting variations in said operating voltage and means for supplying said detected variations to the control electrode of said controllable transistor.
Claim 17
Dependent Claim
34 words
The amplifying circuit of claim 14 wherein said voltage detecting means comprises voltage dividing means connected to said operating voltage supply means and having an output terminal coupled to said controllable transistor control electrode.
Claim 18
Dependent Claim
36 words
The amplifying circuit of claim 14 wherein said first and second load impedance means couple said output terminals of said differentially-connected transistors to the source electrodes of said first and second field effect transistor means, respectively.
Claim 19
Dependent Claim
36 words
The amplifying circuit of claim 14 wherein said first and second load impedance means couple said output terminals of said differentially-connected transistors to the drain electrodes of said first and second field effect transistor means, respectively.
Claim 20
Dependent Claim
56 words
The amplifying circuit of claim 17 wherein each of said first and second load impedance means comprises series-connected resistors for interconnecting the drain and gate electrodes of the associated field effect transistor means; and a capacitor connected between the junction defined by said series-connected resistors and the source electrode of said associated field effect transistor means.
Claim 21
Dependent Claim
74 words
An amplifier circuit comprising: a field effect transistor having a source electrode, a gate electrode and a drain electrode; a first voltage supply connected to said drain electrode; a second voltage supply; a resistor connected between said source electrode and said gate electrode; a constant-current supplying circuitry connected between said gate electrode and said second voltage supply; an input terminal connected to said gate electrode; and an output terminal connected to said source electrode.
Claim 22
Dependent Claim
74 words
An amplifier circuit comprising: a field effect transistor having a source electrode, a gate electrode and a drain electrode; a first voltage supply connected to said drain electrode; a second voltage supply; a resistor connected between said source electrode and said gate electrode; a constant-current supplying circuitry connected between said gate electrode and said second voltage supply; an input terminal connected to said gate electrode; and an output terminal connected to said source electrode.
References Cited (Backward Citations)
US3092783A
Cited
US3750042A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-09 | 1981-07-11 | 1982-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-09 | 1985-07-11 | 1986-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-09 | 1989-07-11 | 1990-01-10 | $7700.00 | Window Closed / Lapsed |