US3612975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic data-processing apparatus
Assignee: IAN YOUNG ELECTRONIC DESIGNS L
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Filing: 1969-08-05
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Granted: 1971-10-12
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Expires: 1989-08-05
Abstract
Abstract In a circuit for converting a signal representing by its amplitude an item of data into a signal representing the item of data by its pulse duration, or vice versa, by comparison of an input signal with a ramp signal, a calibrating signal is applied to the amplitude-to-duration converter and the resulting pulse duration is compared with a calibrating pulse having a duration corresponding, at the required conversion scale, to the amplitude of the calibrating signal; any error signal from the comparator is used to adjust the ramp slope or ramp base line in a sense such as to reduce the error.
Inventors
- 👤 Arthur T Keefe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:52
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/04; G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G05D3/18; G06; G06G; G06G7/00; G06G7/12; G06G7/26; G06G7/28; H03K5/22; H03K5/26; H03M; H03M1/00; H03M1/12; H03M1/50
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
217 words
Apparatus for converting a signal representing by its amplitude an item of data into a signal representing the item of data by its pulse duration, or vice versa, by comparison of an input signal with a ramp signal, including a ramp generator, a voltage comparator for comparing a first voltage input to the comparator with a second voltage input derived from the ramp generator output so as to produce a comparator output signal having a pulse width dependent upon the amplitude of the first voltage input to the comparator, and calibrating means, said calibrating means comprising: means for obtaining a calibrating voltage and applying this calibrating voltage as a first voltage input to said voltage comparator; a clock source; means for deriving a calibrating pulse of known period from said clock source, the known period corresponding, at the required ramp slope, to the amplitude of said calibrating voltage; a pulse period comparator connected to receive said pulse of known period and the pulse output of said voltage comparator, derived from said calibrating voltage, and providing a signal representing the difference in the durations of the two pulse periods; and a ramp-modifying circuit responsive to the pulse period difference signal from said pulse period comparator to modify the ramp in a sense such as to reduce the difference.
Claim 2
Dependent Claim
217 words
Apparatus for converting a signal representing by its amplitude an item of data into a signal representing the item of data by its pulse duration, or vice versa, by comparison of an input signal with a ramp signal, including a ramp generator, a voltage comparator for comparing a first voltage input to the comparator with a second voltage input derived from the ramp generator output so as to produce a comparator output signal having a pulse width dependent upon the amplitude of the first voltage input to the comparator, and calibrating means, said calibrating means comprising: means for obtaining a calibrating voltage and applying this calibrating voltage as a first voltage input to said voltage comparator; a clock source; means for deriving a calibrating pulse of known period from said clock source, the known period corresponding, at the required ramp slope, to the amplitude of said calibrating voltage; a pulse period comparator connected to receive said pulse of known period and the pulse output of said voltage comparator, derived from said calibrating voltage, and providing a signal representing the difference in the durations of the two pulse periods; and a ramp-modifying circuit responsive to the pulse period difference signal from said pulse period comparator to modify the ramp in a sense such as to reduce the difference.
Claim 3
Dependent Claim
79 words
Apparatus in accordance with claim 1, for converting a signal representing by its amplitude an item of data into a signal representing the item of data by its pulse duration, the signal representing data by its amplitude being subject to amplitude fluctuations unrelated to the data represented by that signal, in which the calibrating voltage is subject to the same amplitude fluctuations as the said input signal, the period of the pulse derived from the clock source remaining unchanged.
Claim 4
Dependent Claim
189 words
Apparatus in accordance with claim 1, for converting a signal representing by its duration an item of data into a signal representing the item of data by its amplitude, in which said pulse period comparator is connected to receive firstly the signal representing by its duration an item of data and secondly the pulse output of said voltage comparator and in which the output of said pulse period comparator, and thereby the first voltage input of said voltage comparator, is adjusted until the pulse periods are equal, said first voltage input of said voltage comparator constituting the output signal representing the item of data by its amplitude, the apparatus further comprising a null servosystem connected to receive the said output signal as a control signal and effecting an operation to an extent dependent on the amplitude of said control signal, said null servosystem including for producing a balancing signal a device such that the balancing signal is subject to fluctuations in a supply voltage, and wherein the calibrating voltage is subject to the same fluctuations and the period of the calibRating pulse derived from said clock source remains unchanged.
Claim 5
Dependent Claim
137 words
Apparatus in accordance with claim 1, for use with alternative calibrating voltages having levels representing respectively a peak input voltage to be handled by the circuit and a zero data level, the apparatus being such that a zero data level input signal produces a pulse of finite output width, the ramp modifying circuit including firstly means for adjusting the slope of the output of the ramp generator in accordance with the difference in the durations of the two signals applied to the pulse period comparator, when the calibrating voltage has a level representing the peak input voltage, and secondly alternative means for adjusting the base line of the ramp waveform in accordance with the difference in the durations of the two signals applied to the pulse period comparator, when the calibrating voltage represents the zero data level.
Claim 6
Dependent Claim
38 words
Apparatus in accordance with claim 3, in which the said device for generating a balancing signal is a potentiometer, the wiper of which is adjusted by the null servo system and supplies the balancing signal for the latter.
Claim 7
Dependent Claim
18 words
Apparatus in accordance with claim 1, in which the calibrating voltage is obtained from a standard voltage source.
Claim 8
Dependent Claim
60 words
Apparatus in accordance with claim 1, for use when the calibrating voltage has a level representing a input voltage to be handled by the circuit, the ramp modifying circuit comprising means for adjusting the slope of the output of the ramp generator in accordance with the difference in the durations of the two signals applied to he pulse period comparator.
Claim 9
Dependent Claim
47 words
Apparatus in accordance with claim 7, in which the ramp-modifying circuit includes a capacitor arranged for alternate charging and discharging with a current-modifying element in the charging circuit controlled in accordance with the said difference in the durations of the signals applied to the pulse period comparator.
Claim 10
Dependent Claim
66 words
Apparatus in accordance with claim 1, for use with a calibrating voltage representing a zero data level, the apparatus being such that a zero level input signal produces a pulse of finite output width, the ramp-modifying circuit including means for adjusting the base line of the ramp waveform in accordance with the difference in the durations of the two signals applied to the pulse period comparator.
Claim 11
Dependent Claim
48 words
Apparatus in accordance with claim 9, in which the ramp-modifying circuit includes a capacitor arranged for alternate charging and discharging and means controlling the potential across the capacitor when discharged in accordance with the difference in the durations of the two signals applied to the pulse period comparator.
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) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |