Patent US3872392A successfully refreshed from Google Patents.
US3872392A
Expired / Lapsed
US
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Cascade direct-coupled amplifier
Assignee: Hitachi Ltd
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Filing: 1973-07-26
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Granted: 1975-03-18
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Expires: 1993-07-26
Abstract
Abstract A cascade direct-coupled amplifier comprising a currentabsorbing circuit whose absorption current increases or decreases in proportion to an increase or decrease in the supply voltage of the amplifier, thereby to make the dynamic range of the amplifier wide.
Inventors
- 👤 Yoshio Sakamoto
- 👤 Shinsuke Iguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:29
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; H03F1/302
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
152 words
In a cascade direct-coupled amplifier having a supply voltage source, a first grounded-emitter transistor connected to said supply voltage source, a second grounded-emitter transistor which is connected DC-wise to said first transistor and to said supply voltage source, and a bias circuit which supplies a bias current from the emitter of said second transistor to the base of said first transistor, the improvement comprising current absorbing circuit means for providing an absorption current which varies in proportion to changes in said supply voltage source and which is connected to said emitter of said second transistor, said current absorbing circuit means including a third grounded-emitter transistor having its collector connected to the emitter of said second grounded-emitter transistor, and a resistor and a diode connected in series between said supply voltage source and ground, the base of said third transistor being connected to the point of connection of said resistor and said diode.
Claim 2
Dependent Claim
152 words
In a cascade direct-coupled amplifier having a supply voltage source, a first grounded-emitter transistor connected to said supply voltage source, a second grounded-emitter transistor which is connected DC-wise to said first transistor and to said supply voltage source, and a bias circuit which supplies a bias current from the emitter of said second transistor to the base of said first transistor, the improvement comprising current absorbing circuit means for providing an absorption current which varies in proportion to changes in said supply voltage source and which is connected to said emitter of said second transistor, said current absorbing circuit means including a third grounded-emitter transistor having its collector connected to the emitter of said second grounded-emitter transistor, and a resistor and a diode connected in series between said supply voltage source and ground, the base of said third transistor being connected to the point of connection of said resistor and said diode.
Claim 3
Dependent Claim
24 words
A cascade direcT-coupled amplifier as defined in claim 1, wherein a further resistor is connected between the base and collector of said third transistor.
Claim 4
Dependent Claim
32 words
A cascade direct-coupled amplifier as defined in claim 2, wherein said bias circuit comprises a feed-back resistor connected between the emitter of said second transistor and the base of said first transistor.
Claim 5
Dependent Claim
212 words
A cascade direct-coupled amplifier comprising a supply voltage source, a first transistor having its emitter connected to ground through a first resistor and its collector connected to said supply voltage source, second and third transistors, the base of said second transistor being connected to the collector of said first transistor, the emitter of said second transistor being connected to the base of said third transistor and through a second resistor to the emitter of said third transistor, a parallel circuit of a capacitor and a third resistor connected between the emitter of said third transistor and ground, fourth and fifth resistors connected in series between the collector of said third transistor and said supply voltage source, the collector of said second transistor being connected to the point of connection of said fourth and fifth resistors, a bias circuit which supplies a bias current from the emitter of said third transistor and the base of said first transistor, a fourth transistor having its collector connected to the emitter of said third transistor and its emitter grounded, and a sixth resistor and a diode connected in series between said supply voltage source and ground, the base of said fourth transistor being connected to the point of connection of said sixth resistor and said diode.
Claim 6
Dependent Claim
212 words
A cascade direct-coupled amplifier comprising a supply voltage source, a first transistor having its emitter connected to ground through a first resistor and its collector connected to said supply voltage source, second and third transistors, the base of said second transistor being connected to the collector of said first transistor, the emitter of said second transistor being connected to the base of said third transistor and through a second resistor to the emitter of said third transistor, a parallel circuit of a capacitor and a third resistor connected between the emitter of said third transistor and ground, fourth and fifth resistors connected in series between the collector of said third transistor and said supply voltage source, the collector of said second transistor being connected to the point of connection of said fourth and fifth resistors, a bias circuit which supplies a bias current from the emitter of said third transistor and the base of said first transistor, a fourth transistor having its collector connected to the emitter of said third transistor and its emitter grounded, and a sixth resistor and a diode connected in series between said supply voltage source and ground, the base of said fourth transistor being connected to the point of connection of said sixth resistor and said diode.
Claim 7
Dependent Claim
24 words
A cascade direct-coupled amplifier as defined in claim 4, wherein a seventh resistor is connected between the base and collector of said fourth transistor.
Claim 8
Dependent Claim
32 words
A cascade direct-coupled amplifier as defined in claim 5, wherein said bias circuit comprises an eighth resistor connected between the emitter of said third resistor and the base of said first resistor.
Claim 9
Dependent Claim
66 words
A cascade direct-coupled amplifier as defined in claim 5, further including a fifth transistor and a ninth resistor connected in series between the collector of said first transistor and said supply voltage source, and a sixth transistor and tenth resistor connected in series between the collector of said fourth transistor and said supply voltage source, the bases of said fifth and sixth transistors being connected together.
Claim 10
Dependent Claim
28 words
A cascade direct-coupled amplifier as defined in claim 7, wherein a pair of additional diodes are connected in series between said sixth resistor and said supply voltage source.
References Cited (Backward Citations)
US3424992A
Cited
US3750040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |