US3621402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sampled data filter
Assignee: AT&T Inc
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Filing: 1970-08-03
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Granted: 1971-11-16
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Expires: 1990-08-03
Abstract
Abstract A sampled data filter is disclosed comprising a plurality of amplifiers interconnected by delay units and feedback resistors. Each delay unit comprises the cascade connection of actuable switches and storage capacitors. The values of the capacitors and feedback resistors are preselected to obtain a desired transfer function and to nullify the effects of residual capacitor charge.
Inventors
- 👤 William Allen Gardner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:02
CPC Classifications
H; H03; H03H; H03H15/00; H03H15/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
167 words
A sampled data filter comprising: a first amplifier responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier, comprising a plurality of actuable switches connecting a plurality of storage capacitors; a second amplifier responsive to the output signal of said first delay means; second delay means, responsive to the output signal of said second amplifier, comprising a plurality of actuable switches connecting a plurality of storage capacitors; first feedback means connecting the input and output of said first amplifier; second feedback means connecting the input and of said second amplifier; third feedback means connecting the output of said first delay means to the input of said first amplifier; fourth feedback means connecting the output of said second delay means to the input of said second amplifier; fifth feedback means connecting the output of said second delay means to the input of said first amplifier; and means for selectively actuating the respective switches of said first and second delay means.
Claim 2
Dependent Claim
167 words
A sampled data filter comprising: a first amplifier responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier, comprising a plurality of actuable switches connecting a plurality of storage capacitors; a second amplifier responsive to the output signal of said first delay means; second delay means, responsive to the output signal of said second amplifier, comprising a plurality of actuable switches connecting a plurality of storage capacitors; first feedback means connecting the input and output of said first amplifier; second feedback means connecting the input and of said second amplifier; third feedback means connecting the output of said first delay means to the input of said first amplifier; fourth feedback means connecting the output of said second delay means to the input of said second amplifier; fifth feedback means connecting the output of said second delay means to the input of said first amplifier; and means for selectively actuating the respective switches of said first and second delay means.
Claim 3
Dependent Claim
41 words
The sampled data filter of claim 1 further comprising: a third amplifier responsive to the output signals of said first amplifier and said first and second delay means; and sixth feedback means connecting the input and output of said third amplifier.
Claim 4
Dependent Claim
75 words
The sampled data filter of claim 1 further comprising: a third amplifier; first circuit means for applying the output signal of said first amplifier to said third amplifier; second circuit means for applying the output signal of said first delay means to said third amplifier; third circuit means for applying the output signal of said second delay means to said third amplifier; and sixth feedback means connecting the input and output of said third amplifier.
Claim 5
Dependent Claim
84 words
A sampled data filter comprising: first amplifier means responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier means, comprising a plurality of actuable switches connecting a plurality of storage capacitors; first feedback means connecting the input and output of said first amplifier means; second feedback means connecting the output of said first delay means to the input of said first amplifier means; and control means for selectively actuating the respective switches of said delay means.
Claim 6
Dependent Claim
84 words
A sampled data filter comprising: first amplifier means responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier means, comprising a plurality of actuable switches connecting a plurality of storage capacitors; first feedback means connecting the input and output of said first amplifier means; second feedback means connecting the output of said first delay means to the input of said first amplifier means; and control means for selectively actuating the respective switches of said delay means.
Claim 7
Dependent Claim
115 words
The sampled data filter of claim 4 further comprising: second amplifier means responsive to the output of said first delay means; second delay means, responsive to the output signal of said second amplifier means, comprising a plurality of actuable switches connecting a plurality of storage capacitors; third feedback means connecting the input and output of said second amplifier means; fourth feedback means connecting the output of said second delay means to the input of said second amplifier means; fifth feedback means connecting the output of said second delay means to the input of said first amplifier means; and means responsive to said control means for selectively actuating the respective switches of said second delay means.
Claim 8
Dependent Claim
42 words
The sampled data filter of claim 5 further comprising: third amplifier means responsive to the output signals of said first amplifier means and said first and second delay means; and sixth feedback means connecting the input and output of said third amplifier.
Claim 9
Dependent Claim
186 words
A sampled data filter comprising: a first amplifier responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier, comprising the serial connection of a first switch, a first capacitor, a second switch a second capacitor, and a third switch; a second amplifier responsive to the output signal of said first delay means; second delay means, responsive to the output signal of said second amplifier, comprising the serial connection of a first switch, a first capacitor, a second switch, a second capacitor and a third switch; first resistor means connecting the input and output of said first amplifier; second resistor means connecting the input and output of said second amplifier; third resistor means connecting the output of said first delay means to the input of said first amplifier; fourth resistor means connecting the output of said second delay means to the input of said second amplifier; fifth resistor means connecting the output of said second delay means to the input of said first amplifier; and means for selectively operating the respective switches of said first and second delay means.
Claim 10
Dependent Claim
186 words
A sampled data filter comprising: a first amplifier responsive to an applied input signal; first delay means, responsive to the output signal of said first amplifier, comprising the serial connection of a first switch, a first capacitor, a second switch a second capacitor, and a third switch; a second amplifier responsive to the output signal of said first delay means; second delay means, responsive to the output signal of said second amplifier, comprising the serial connection of a first switch, a first capacitor, a second switch, a second capacitor and a third switch; first resistor means connecting the input and output of said first amplifier; second resistor means connecting the input and output of said second amplifier; third resistor means connecting the output of said first delay means to the input of said first amplifier; fourth resistor means connecting the output of said second delay means to the input of said second amplifier; fifth resistor means connecting the output of said second delay means to the input of said first amplifier; and means for selectively operating the respective switches of said first and second delay means.
Claim 11
Dependent Claim
41 words
The sampled data filter of claim 7 further comprising: a third amplifier responsive to the output signals of said first amplifier and said first and second delay means; and sixth resistor means connecting the input and output of said third amplifier.
Claim 12
Dependent Claim
75 words
The sampled data filter of claim 7 further comprising: a third amplifier; sixth resistor means for applying the output signal of said first amplifier to said third amplifier; seventh resistor means for applying the output signal of said first delay means to said third amplifier; eighth resistor means for applying the output signal of said second delay means to said third amplifier; and ninth resistor means connecting the input and output of said third amplifier.
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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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |