US6028487A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Negative-feedback amplifier circuit capable of independently controlling a gain and an impedance
Assignee: Renesas Electronics Corp
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Filing: 1997-09-29
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Granted: 2000-02-22
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Expires: 2017-09-29
Abstract
Abstract A plurality of field effect transistors (FET's) (11, 12) are coupled in cascode connection. A drain of the final-stage FET (12) is coupled to a gate of the first-stage FET (11) through a first negative-feedback circuit (13). A drain of the first-stage FET (11) is coupled to the gate of the first-stage FET (11) through a second negative-feedback circuit (14). The first negative-feedback circuit (13) is connected to a first resistor (Rf1) while the second negative-feedback circuit (14) is connected to a second resistor (Rf2).
Inventors
- 👤 Yuji Kakuta
- 👤 Yasuhiro Shirakawa
- 👤 Yoshiaki Fukasawa
- 👤 Yoshiaki Wakabayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:50
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/08; H03F1/22; H03F1/223
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
181 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of active elements in cascode connection, said active elements including a first-stage active element and a final-stage active element each of which comprises an element input terminal, an element output terminal, and an element control terminal, said element control terminal of the first-stage active element being supplied with said input electric signal, said element output terminal of the final-stage active element outputting said output electric signal; a first negative-feedback circuit connected between said element output terminal of the final-stage active element and said element control terminal of the first-stage active element, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said element output terminal of the first-stage active element and said element control terminal of the first-stage active element, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 2
Dependent Claim
181 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of active elements in cascode connection, said active elements including a first-stage active element and a final-stage active element each of which comprises an element input terminal, an element output terminal, and an element control terminal, said element control terminal of the first-stage active element being supplied with said input electric signal, said element output terminal of the final-stage active element outputting said output electric signal; a first negative-feedback circuit connected between said element output terminal of the final-stage active element and said element control terminal of the first-stage active element, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said element output terminal of the first-stage active element and said element control terminal of the first-stage active element, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 3
Dependent Claim
153 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of FETs in cascode connection, said FETs including a first-stage FET and final stage FET each of which comprises a source, a drain, and a gate, said gate of the first-stage FET being supplied with said input electric signal, said drain o fth final-stage FET outputting said output electric signal; a first negative-feedback circuit connected between said drain of the final-stage FET and said gate of the first-stage FET, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said drain of the first-stage FET and said gate of the first-stage FET, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 4
Dependent Claim
153 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of FETs in cascode connection, said FETs including a first-stage FET and final stage FET each of which comprises a source, a drain, and a gate, said gate of the first-stage FET being supplied with said input electric signal, said drain o fth final-stage FET outputting said output electric signal; a first negative-feedback circuit connected between said drain of the final-stage FET and said gate of the first-stage FET, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said drain of the first-stage FET and said gate of the first-stage FET, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 5
Dependent Claim
164 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of bipolar transistors in cascode connection, said bipolar transistors including a first-stage bipolar transistor and a final stage bipolar transistor each of which comprises an emitter, a collector, and a base, said base of the first-stage bipolar transistor being supplied with said input electric signal, said collector of the final-stage bipolar transistor outputting said output electric signal; a first negative-feedback circuit connected between said collector of the final-sage bipolar transistor and said base of the first-stage bipolar transistor, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said collector of the first-stage bipolar transistor and the base of the first-stage bipolar transistor, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 6
Dependent Claim
164 words
A negative-feedback amplifier circuit for amplifying an input electric signal into an output electric signal, comprising: a plurality of bipolar transistors in cascode connection, said bipolar transistors including a first-stage bipolar transistor and a final stage bipolar transistor each of which comprises an emitter, a collector, and a base, said base of the first-stage bipolar transistor being supplied with said input electric signal, said collector of the final-stage bipolar transistor outputting said output electric signal; a first negative-feedback circuit connected between said collector of the final-sage bipolar transistor and said base of the first-stage bipolar transistor, said first negative-feedback circuit including a means for adjusting an output impedance of said negative-feedback amplifier circuit; and a second negative-feedback circuit connected between said collector of the first-stage bipolar transistor and the base of the first-stage bipolar transistor, wherein said first negative-feedback circuit returns negative feedback to said element control terminal of the first-stage active element without limiting said negative feedback to a predetermined range of frequencies.
Claim 7
Dependent Claim
29 words
A negative-feedback amplifier circuit as claimed in claim 1, wherein said means includes a first resistor having a value which determines the output impedance of said negative-feedback amplifier circuit.
Claim 8
Dependent Claim
41 words
A negative-feedback amplifier circuit as claimed in claim 2, wherein said first negative-feedback circuit comprises a first resistor for adjusting an output impedance, said second negative-feedback circuit comprising a second resistor for adjusting a gain in cooperation with said first resistor.
Claim 9
Dependent Claim
41 words
A negative-feedback amplifier circuit as claimed in claim 3, wherein said first negative-feedback circuit comprises a first resistor for adjusting an output impedance, said second negative-feedback circuit comprising a second resistor for adjusting a gain in cooperation with said first resistor.
Claim 10
Dependent Claim
31 words
A negative-feedback amplifier circuit as claimed in any one of claims 4-6, wherein said second negative-feedback circuit includes a second resistor for adjusting a gain in cooperation with said first resistor.
Claim 11
Dependent Claim
29 words
A negative-feedback amplifier circuit as claimed in claim 2, wherein said means includes a first resistor having a value which determines the output impedance of said negative-feedback amplifier circuit.
Claim 12
Dependent Claim
29 words
A negative-feedback amplifier circuit as claimed in claim 3, wherein said means includes a first resistor having a value which determines the output impedance of said negative-feedback amplifier circuit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-02-21 | 2003-08-23 | 2004-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-02-21 | 2007-08-23 | 2008-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-02-21 | 2011-08-23 | 2012-02-22 | $7700.00 | Window Closed / Lapsed |