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Patent US3225345A successfully refreshed from Google Patents.
US3225345A
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Assignee: Unisys Corp
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Filing: 1961-04-11
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Granted: 1965-12-21
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Expires: 1981-04-11
Abstract
No abstract record available.
Inventors
- 👤 Absatz Seymour
- 👤 Jr John Lewis Cifu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:50
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
166 words
IN A DIGITAL TO ANALOG CONVERTER OF THE CHARACTER DESCRIBED, A SOURCE OF DIGITAL INFORMATION INCLUDING A COMPUTER, A DIGITAL INPUT CIRCUITRY WHICH COMPRISES; A PLURALITY OF "AND" GATES WHICH ARE ADAPTED TO RECEIVE DIGITAL INFORMATION IMPARTED THERETO IN BINARY FORM FROM SAID SOURCE OF INFORMATION IN ACCORDANCE WITH THE MAGNITUDE OF THE INFORMATION BEING IMPARTED, A PLURALITY OF TRANSISTORS ONE EACH OF WHICH CONNECTED TO EACH OF "AND" GATES BY A CONDUCTIVE THROUGH WHICH THE INFORMATION IMPARTED TO SAID "AND" GATES FED TO BASE ELECTRODES OF SAID TRANSISTOR, EACH OF THE EMITTERS OF SAID TRANSISTORS BEING CONNECTED TO A GROUND THROUGH AN EMITTER RESISTOR, AND EACH OF THE COLLECTORS OF SAID TRANSISTORS BEING CONNECTED TO CONDUCTOR MEANS THROUGH WHICH A LOW COLLECTOR VOLTAGE IS CONSTANTLY APPLIED, SAID EMITTER RESISTORS BEING SO SELECTED THAT EACH ONE THEREOF PROPORTIONATELY WEIGHTS THE BINARY INPUT INFORMATION IMPARTED THERETO; AN A.C. AMPLIFIER; MEANS BY WHICH SAID DIGITAL INFORMATION IS IMPARTED TO SAID AMPLIFIER IN A.C. FORM; A FULL WAVE DEMODULATOR,
Claim 2
Dependent Claim
166 words
IN A DIGITAL TO ANALOG CONVERTER OF THE CHARACTER DESCRIBED, A SOURCE OF DIGITAL INFORMATION INCLUDING A COMPUTER, A DIGITAL INPUT CIRCUITRY WHICH COMPRISES; A PLURALITY OF "AND" GATES WHICH ARE ADAPTED TO RECEIVE DIGITAL INFORMATION IMPARTED THERETO IN BINARY FORM FROM SAID SOURCE OF INFORMATION IN ACCORDANCE WITH THE MAGNITUDE OF THE INFORMATION BEING IMPARTED, A PLURALITY OF TRANSISTORS ONE EACH OF WHICH CONNECTED TO EACH OF "AND" GATES BY A CONDUCTIVE THROUGH WHICH THE INFORMATION IMPARTED TO SAID "AND" GATES FED TO BASE ELECTRODES OF SAID TRANSISTOR, EACH OF THE EMITTERS OF SAID TRANSISTORS BEING CONNECTED TO A GROUND THROUGH AN EMITTER RESISTOR, AND EACH OF THE COLLECTORS OF SAID TRANSISTORS BEING CONNECTED TO CONDUCTOR MEANS THROUGH WHICH A LOW COLLECTOR VOLTAGE IS CONSTANTLY APPLIED, SAID EMITTER RESISTORS BEING SO SELECTED THAT EACH ONE THEREOF PROPORTIONATELY WEIGHTS THE BINARY INPUT INFORMATION IMPARTED THERETO; AN A.C. AMPLIFIER; MEANS BY WHICH SAID DIGITAL INFORMATION IS IMPARTED TO SAID AMPLIFIER IN A.C. FORM; A FULL WAVE DEMODULATOR,
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-12-20 | 1969-06-21 | 1969-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-20 | 1973-06-21 | 1973-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-20 | 1977-06-21 | 1977-12-21 | $7700.00 | Window Closed / Lapsed |