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Patent US4174539A successfully refreshed from Google Patents.
US4174539A
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Magnetic bubble memory detector-amplifier
Assignee: SK Hynix Inc
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Filing: 1978-11-01
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Granted: 1979-11-13
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Expires: 1998-11-01
Abstract
Abstract A magnetic bubble memory detector-amplifier for use with a bubble memory device having the dual output from an active and a dummy bubble detector in combination consists of a differential amplifier associated with constant current sources to drive the bubble detector elements, a notch filter coupled to the output of the differential amplifier to eliminate the rotating magnetic field frequency component, an amplifier coupled to the output of the filter which is controlled by a bias pulse at the fundamental frequency of operation to provide a reference for better discrimination between "ones" and "zeros," and, finally, a self-biasing detector coupled with a strobed output flip-flop.
Inventors
- 👤 Walter C. Timm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:13
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0866
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
138 words
A detector-amplifier for bubble memory devices of the type having a dual output, one dummy and one active, comprising: a differential amplifier, including a constant current source associated with each input and adapted to be connected with respective outputs of a bubble memory device, a notch filter coupled to the output of said differential amplifier and tuned to eliminate signals at the frequency of the rotating magnetic field of a bubble memory device to be associated therewith, an amplifier means connected with the output of said notch filter and including means responsive to a bias pulse to increase the gain of said amplifier, a self biasing detector coupled to the output of said amplifier means, and flip-flop means coupled to the output of said detector and including means responsive to a strobe pulse for gating an output signal.
Claim 2
Dependent Claim
138 words
A detector-amplifier for bubble memory devices of the type having a dual output, one dummy and one active, comprising: a differential amplifier, including a constant current source associated with each input and adapted to be connected with respective outputs of a bubble memory device, a notch filter coupled to the output of said differential amplifier and tuned to eliminate signals at the frequency of the rotating magnetic field of a bubble memory device to be associated therewith, an amplifier means connected with the output of said notch filter and including means responsive to a bias pulse to increase the gain of said amplifier, a self biasing detector coupled to the output of said amplifier means, and flip-flop means coupled to the output of said detector and including means responsive to a strobe pulse for gating an output signal.
Claim 3
Dependent Claim
29 words
The detector-amplifier of claim 1 wherein said notch filter is comprised of a series tuned capacitor-inductor network connected between the output of said differential amplifier and a ground reference.
Claim 4
Dependent Claim
37 words
The detector-amplifier of claim 1 wherein said amplifier means is a differential amplifier and further comprising a series coupled resistor-capacitor network coupled across the inputs thereof to enhance the second harmonic signal of a detected magnetic bubble.
Claim 5
Dependent Claim
61 words
The detector-amplifier of claim 1 wherein said self biasing detector is comprised of a resistor and diode in parallel coupled to the output of said amplifier means at one connecting point thereof, a capacitor connected to the other connecting point of the resistor and diode in parallel, said capacitor being connected to an amplifier means and biasing means for said diode.
References Cited (Backward Citations)
US3813660A
Cited
US3953840A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-11-12 | 1983-05-14 | 1983-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-12 | 1987-05-14 | 1987-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-12 | 1991-05-14 | 1991-11-13 | $7700.00 | Window Closed / Lapsed |