US4728902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilized cascode amplifier
Assignee: Vermont Technical College
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Filing: 1986-09-08
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Granted: 1988-03-01
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Expires: 2006-09-08
Abstract
Abstract A bipolar integrated circuit amplifier with a cascode stage has an emitter follower biasing circuit which provides a bias voltage to the cascode stage. The cascode amplifier stage is stabilized by providing a stabilization capacitance across the base-collector junction of the emitter follower in the biasing circuit.
Inventors
- 👤 Jeffrey Gleason
- 👤 Richard E. Hester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:56
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; H03F3/45085; H03F3/45089; H03F1/00; H03F1/08; H03F1/083; H03F2203/00; H03F2203/45; H03F2203/45398
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
78 words
A bipolar integrated circuit amplifier having a cascode stage which receives a bias voltage from an emitter-follower bias circuit which includes a transistor having a base, an emitter and a collector, means for providing a base voltage to the base of the transistor, means for deriving the bias voltage from the emitter of the transistor, and stabilization capacitance means between the base and collector of the transistor for stabilizing the cascode stage of the bipolar integrated circuit amplifier.
Claim 2
Dependent Claim
78 words
A bipolar integrated circuit amplifier having a cascode stage which receives a bias voltage from an emitter-follower bias circuit which includes a transistor having a base, an emitter and a collector, means for providing a base voltage to the base of the transistor, means for deriving the bias voltage from the emitter of the transistor, and stabilization capacitance means between the base and collector of the transistor for stabilizing the cascode stage of the bipolar integrated circuit amplifier.
Claim 3
Dependent Claim
22 words
The invention of claim 1 wherein the stabilization capacitance means has a capacitance of between about 1 pf and about 100 pf.
Claim 4
Dependent Claim
17 words
The invention of claim 1 wherein the stabilzation capacitance means has a capacitance of about 4 pf.
Claim 5
Dependent Claim
24 words
The invention of claim 1 wherein the means for providing a base voltage includes a voltage divider connected between first and second supply terminals.
Claim 6
Dependent Claim
29 words
The invention of claim 4 wherein the transistor has its collector connected to the first supply terminal and its emitter connected through a load to the second supply terminal.
Claim 7
Dependent Claim
18 words
The invention of claim 1 wherein the amplifier has a differential amplifier stage connected to the cascode stage.
Claim 8
Dependent Claim
43 words
The invention of claim 6 wherein the differential amplifier stage includes first and second differential stage transistors having bases connected to first and second input terminals, respectively; having emitters connected together to a current source; and having collectors connected to the cascode stage.
Claim 9
Dependent Claim
44 words
The invention of claim 7 wherein the cascode stage includes first and second cascode stage transistors having bases connected to the bias circuit to receive the bias voltage and having emitters connected to the collectors of the first and second differential stage transistors, respectively.
Claim 10
Dependent Claim
27 words
The invention of claim 8 wherein the first and second cascode stage transistors have collectors connected through first and second resistance means to a first supply terminal.
Claim 11
Dependent Claim
27 words
The invention of claim 9 wherein the first and second differential stage transistors are NPN transistors and the first and second cascode stage transistors are NPN transistors.
Claim 12
Dependent Claim
15 words
The invention of claim 10 wherein the transistor of the bias is an NPN transistor.
Claim 13
Dependent Claim
14 words
The invention of claim 1 wherein the stabilzation capacitance means is a junction capacitor.
References Cited (Backward Citations)
US3991381A
Cited
US4528517A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |