Patent US3660768A successfully refreshed from Google Patents.
US3660768A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Precision rectifier with improved transient response
Assignee: AT&T Inc
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Filing: 1970-12-21
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Granted: 1972-05-02
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Expires: 1990-12-21
Abstract
Abstract A precision rectifier circuit rectifies voltage signals near zero without a loss in transient response. This is accomplished by reducing the gain of the amplifier with an additional feedback resistor. The error in the output current caused by this resistor is canceled by supplying additional current from the amplifier to the rectifier output through a second rectifier and a resistor.
Inventors
- 👤 Carl Leslie Dammann
- 👤 Frederick Alan Saal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:10
CPC Classifications
H; H03; H03D; H03D1/00; H03D1/02; H03D1/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
202 words
A rectifier circuit having an output which is connected to a summing junction and an input comprising: a first operational amplifier having an input and an output, a first input resistance connected between the circuit input and the input of said first amplifier, a first feedback diode having its anode connected to the output of said first amplifier, a first feedback resistance connected between the cathode of said first feedback diode and the input of said first amplifier, a second feedback diode having its cathode connected to the output of said first amplifier, a second feedback resistance connected between the anode of said second feedback diode and the input of said first amplifier, a first output resistance connected between the cathode of said first diode and the circuit output, a second output resistance connected between the input and output of the circuit, a third feedback resistance connected between the input and output of said first amplifier, and a variable resistance means connected between the output of said first amplifier and the output of the cirCuit, said variable resistance means providing a relatively infinite resistance when the voltage at the circuit input is positive and a finite resistance when the voltage is negative.
Claim 2
Dependent Claim
202 words
A rectifier circuit having an output which is connected to a summing junction and an input comprising: a first operational amplifier having an input and an output, a first input resistance connected between the circuit input and the input of said first amplifier, a first feedback diode having its anode connected to the output of said first amplifier, a first feedback resistance connected between the cathode of said first feedback diode and the input of said first amplifier, a second feedback diode having its cathode connected to the output of said first amplifier, a second feedback resistance connected between the anode of said second feedback diode and the input of said first amplifier, a first output resistance connected between the cathode of said first diode and the circuit output, a second output resistance connected between the input and output of the circuit, a third feedback resistance connected between the input and output of said first amplifier, and a variable resistance means connected between the output of said first amplifier and the output of the cirCuit, said variable resistance means providing a relatively infinite resistance when the voltage at the circuit input is positive and a finite resistance when the voltage is negative.
Claim 3
Dependent Claim
146 words
A circuit as claimed in claim 1, wherein said variable resistance means comprises: a second operational amplifier having an input and an output, a second input resistance connected between the output of said first amplifier and the input of said second amplifier, a third feedback diode having its anode connected to the output of said second amplifier, a fourth feedback resistance connected between the cathode of said third feedback diode and the input of said second amplifier, a fourth feedback diode having its cathode connected to the output of said second amplifier, a fifth feedback resistance connected between the anode of said fourth feedback diode and the input of said second amplifier, a third output resistance connected between the cathode of said third feedback diode and the circuit output, and a fourth output resistance connected between the output of said first amplifier and the circuit output.
Claim 4
Dependent Claim
22 words
A circuit as claimed in claim 2 wherein said third feedback resistance is substantially larger in value than said first feedback resistance.
Claim 5
Dependent Claim
25 words
A circuit as claimed in claim 2 wherein said first input resistance, said first output resistance, and said second output resistance are equal in value.
Claim 6
Dependent Claim
32 words
A circuit as claimed in claim 4 wherein said first feedback resistance and said second feedback resistance are equal in value and equal to twice the value of said first input resistance.
Claim 7
Dependent Claim
25 words
A circuit as claimed in claim 2 wherein said second input resistance, said fourth feedback resistance, and said fifth feedback resistance are equal in value.
Claim 8
Dependent Claim
32 words
A circuit as claimed in claim 2 wherein said third output resistance and said fourth output resistance are equal in value and equal to one-half the value of said third feedback resistance.
References Cited (Backward Citations)
US3553566A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |