Patent US3678296A successfully refreshed from Google Patents.
US3678296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical signal slope polarity change detector
Assignee: American Optical Corp
•
Filing: 1970-04-14
•
Granted: 1972-07-18
•
Expires: 1990-04-14
Abstract
Abstract An electrical signal slope polarity change detector. A circuit for detecting changes in slope polarity of an electrical input signal and for providing an output indication of each slope polarity change. The circuit utilizes an amplifier with negative feedback which changes substantially its value of feedback impedance during a change in slope polarity of the input signal. The input signal is capacitively coupled to the amplifier input. The circuit is, within limits, insensitive to input signal variations in amplitude, frequency, and offset level.
Inventors
- 👤 Christopher C Day
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:46
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/08; A61B5/085; A61B5/086; H; H03; H03K; H03K5/00; H03K5/153; H03K5/1532
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
116 words
A slope reversal detector for detecting changes in the polarity of the slope of an input signal comprising operational amplifier means having an output terminal and inverting and noninverting input terminals; reference potential source means connected to said non-inverting input terminal; capacitor means for coupling an input signal to said inverting input terminal; and feedback means connected between said output terminal and said inverting input terminal; said feedback means including breakdown means and being operative to present a very low impedance when the potential of either polarity across it exceeds a predetermined breakdown magnitude and to present a very high impedance when the potential of either polarity across it is less than said predetermined breakdown magnitude.
Claim 2
Dependent Claim
116 words
A slope reversal detector for detecting changes in the polarity of the slope of an input signal comprising operational amplifier means having an output terminal and inverting and noninverting input terminals; reference potential source means connected to said non-inverting input terminal; capacitor means for coupling an input signal to said inverting input terminal; and feedback means connected between said output terminal and said inverting input terminal; said feedback means including breakdown means and being operative to present a very low impedance when the potential of either polarity across it exceeds a predetermined breakdown magnitude and to present a very high impedance when the potential of either polarity across it is less than said predetermined breakdown magnitude.
Claim 3
Dependent Claim
31 words
A slope reversal detector in accordance with claim 1 wherein said breakdown means includes a pair of oppositely poled Zener diodes connected between said output terminal and said inverting input terminal.
Claim 4
Dependent Claim
33 words
A slope reversal detector in accordance with claim 1 wherein said feedback means includes a pair of oppositely poled Zener diodes connected in series between said output terminal and said inverting input terminal.
Claim 5
Dependent Claim
39 words
A slope reversal detector in accordance with claim 1 wherein the potential of said reference potential source means is ground, and positive and negative potentials at said output terminal represent respectively negative and positive slopes of said input signal.
References Cited (Backward Citations)
US2861239A
Cited
US3347223A
Cited
US3340867A
Cited
US3433217A
Cited
US3524058A
Cited
US3532087A
Cited
US3536062A
Cited
US3545429A
Cited
US3572317A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |