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Patent US3801924A successfully refreshed from Google Patents.
US3801924A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential amplifier
Assignee: Halliburton Co
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Filing: 1972-08-14
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Granted: 1974-04-02
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Expires: 1992-08-14
Abstract
Abstract A differential amplifier used as a line receiver for time multiplexed analog signals is shown. The normal amplification operation of the amplifier is cut off at predetermined intervals and the amplifier is reset.
Inventors
- 👤 H Mueller
- 👤 W Voigt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:39
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; H03F1/303
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
143 words
A differential amplifier for amplifying an analog input signal comprising: a. means for receiving said analog input signal, b. amplifying means normally connected to said receiving means for amplifying said analog input signal, c. means for disconnecting said amplifying means from receiving means at predetermined periods of time, d. a high gain ac coupled amplifier, means for connecting said high gain ac coupled amplifier to the output of said amplifying means a predetermined period of time after said amplifying means has been disconnected from receiving means for sensing the D.C. offset voltage from the output of said amplifying means, and e. a hold amplifier having a capacitor on its input connected to the output of said high gain ac coupled amplifier for applying a compensating signal to the inverting input of said amplifying means to cancel the offset voltage from said amplifying means.
Claim 2
Dependent Claim
143 words
A differential amplifier for amplifying an analog input signal comprising: a. means for receiving said analog input signal, b. amplifying means normally connected to said receiving means for amplifying said analog input signal, c. means for disconnecting said amplifying means from receiving means at predetermined periods of time, d. a high gain ac coupled amplifier, means for connecting said high gain ac coupled amplifier to the output of said amplifying means a predetermined period of time after said amplifying means has been disconnected from receiving means for sensing the D.C. offset voltage from the output of said amplifying means, and e. a hold amplifier having a capacitor on its input connected to the output of said high gain ac coupled amplifier for applying a compensating signal to the inverting input of said amplifying means to cancel the offset voltage from said amplifying means.
Claim 3
Dependent Claim
25 words
The invention claimed in claim 1 including a common mode rejection amplifier connected between said hold amplifier and said amplifier to provide common mode rejection.
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) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |