US4322688A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cascode feed-forward amplifier
Assignee: Tektronix Inc
•
Filing: 1979-10-11
•
Granted: 1982-03-30
•
Expires: 1999-10-11
Abstract
Abstract The cascode feed forward amplifier is modified to correct alpha-induced error. A pair of resistors are serially disposed between the bases of a pair of common-base amplifiers to generate an error voltage proportional to the input signal. The error voltage is applied to the correction amplifier to provide an appropriate correction current.
Inventors
- 👤 Kenneth G. Schlotzhauer
- 👤 Arthur J. Metz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:08
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45076; H03F3/4508; H03F3/45098; H03F3/45103; H03F1/00; H03F1/32; H03F1/3211
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
145 words
A feed-forward amplifier, comprising: a main amplifier comprising an emitter coupled pair of transistors for converting an input signal to a differential signal current; a common-base amplifier stage coupled to said main amplifier, said common-base amplifier stage comprising a pair of transistors through which said differential signal current passes; a correction amplifier having a pair of inputs coupled between said main amplifier and said common-base amplifier stage, and a pair of outputs cross-coupled in a current-aiding sense with the outputs of said common-base amplifier; and means for altering the conduction of said correction amplifier to compensate for alpha-induced error in the differential signal current path, said means comprising a pair of resistors having a predetermined resistance value serially disposed between the bases of said pair of transistors of said common-base amplifier stage, across which resistors an error voltage proportional to said input signal is developed.
Claim 2
Dependent Claim
145 words
A feed-forward amplifier, comprising: a main amplifier comprising an emitter coupled pair of transistors for converting an input signal to a differential signal current; a common-base amplifier stage coupled to said main amplifier, said common-base amplifier stage comprising a pair of transistors through which said differential signal current passes; a correction amplifier having a pair of inputs coupled between said main amplifier and said common-base amplifier stage, and a pair of outputs cross-coupled in a current-aiding sense with the outputs of said common-base amplifier; and means for altering the conduction of said correction amplifier to compensate for alpha-induced error in the differential signal current path, said means comprising a pair of resistors having a predetermined resistance value serially disposed between the bases of said pair of transistors of said common-base amplifier stage, across which resistors an error voltage proportional to said input signal is developed.
Claim 3
Dependent Claim
65 words
An amplifier in accordance with claim 1 wherein said pairs of transistors of said main amplifier and said common base amplifier have equal alpha (α) characteristics, and said pair of resistors each have a value equal to ##EQU3## where R M is the resistance between the emitters of said pair of transistors of said main amplifier, and R S is the input signal source resistance.
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) | 1985-03-29 | 1985-09-28 | 1986-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-29 | 1989-09-28 | 1990-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-29 | 1993-09-28 | 1994-03-30 | $7700.00 | Window Closed / Lapsed |