US4827133A
Expired / Lapsed
US
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Infrared space surveillance detector circuit
Assignee: Richard Hirschmann Radiotechnisches Werk
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Filing: 1986-10-20
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Granted: 1989-05-02
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Expires: 2006-10-20
Abstract
Abstract A circuit layout for an infrared space surveillance detector with a sensor and a field effect transistor following the sensor. An operational amplifier with a negative input is connected to the drain electrode of a field effect transistor. The output signal of the operational amplifier is fed back to its negative input. The stabilization of the operating voltage by the operational amplifier is utilized and the drain electrode of the field effect transistor may be supplied with a stable voltage, so that filtering of the operating voltage by a filter factor of 100 to 120 dB, that would otherwise be required, may be eliminated. It is possible further to apply a constant current and/or regulate the current supplied by utilizing the output signal of the operational amplifier to the source electrode of the field effect transistor.
Inventors
- 👤 Hermann Zierhut
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:53
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/18; G08B13/189; G08B13/19
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
63 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; and a negative feedback operational amplifier stage connected to a drain electrode of said FET; the drain electrode of said FET connected to and biased by the output of said amplifier stage and connected to and providing an inverting input of said amplifier stage.
Claim 2
Dependent Claim
63 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; and a negative feedback operational amplifier stage connected to a drain electrode of said FET; the drain electrode of said FET connected to and biased by the output of said amplifier stage and connected to and providing an inverting input of said amplifier stage.
Claim 3
Dependent Claim
15 words
A circuit according to claim 1 wherein said operational amplifier exhibits a high input impedance.
Claim 4
Dependent Claim
20 words
A circuit according to claim 2 further comprising: a constant current source connected to a source terminal of said FET.
Claim 5
Dependent Claim
24 words
A circuit according to claim 3 wherein an output of said operational amplifier is connected to a control input of said constant current source.
Claim 6
Dependent Claim
15 words
A circuit according to claim 4 wherein said constant current source is a feedback quadripole.
Claim 7
Dependent Claim
21 words
A circuit according to claim 5 wherein said feedback quadripole is an integrated element for attenuation of said operational amplifier output.
Claim 8
Dependent Claim
25 words
A circuit according to claim 5 wherein an attenuation element of said feedback quadripole exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
Claim 9
Dependent Claim
15 words
A circuit according to claim 3 wherein said constant current source is a feedback quadripole.
Claim 10
Dependent Claim
21 words
A circuit according to claim 8 wherein said feedback quadripole is an integrated element for attenuation of said operational amplifier output.
Claim 11
Dependent Claim
25 words
A circuit according to claim 9 wherein an attenuation element of said feedback quadripole exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
Claim 12
Dependent Claim
44 words
A space surveillance detector circuit comprising: a sensor; an FET stage responsive to said sensor; and a current amplification stage responsive to a drain electrode of said FET stage and providing biasing for said FET stage from an output of said current amplification stage.
Claim 13
Dependent Claim
44 words
A space surveillance detector circuit comprising: a sensor; an FET stage responsive to said sensor; and a current amplification stage responsive to a drain electrode of said FET stage and providing biasing for said FET stage from an output of said current amplification stage.
Claim 14
Dependent Claim
16 words
A circuit according to claim 11 wherein said current amplification stage comprises an operational amplifier network.
Claim 15
Dependent Claim
16 words
A circuit according to claim 12 wherein said operational amplifier network exhibits a high input impedance.
Claim 16
Dependent Claim
14 words
A circuit according to claim 13 wherein said sensor is an infrared radiation sensor.
Claim 17
Dependent Claim
15 words
A circuit according to claim 14 wherein said FET stage comprises a constant current source.
Claim 18
Dependent Claim
16 words
A circuit according to claim 15 wherein said constant current source is a four pole network.
Claim 19
Dependent Claim
24 words
A circuit according to claim 16 wherein said four pole network is an integrating amplifier responsive to an output of said current amplification stage.
Claim 20
Dependent Claim
21 words
A circuit according to claim 17 wherein said integrating amplifier exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
Claim 21
Dependent Claim
49 words
An infrared space surveillance circuit comprising: a sensor; an FET connected to said sensor; means for suppressing drain voltage fluctuations connected to a drain terminal output of said FET wherein said means for suppressing includes a negative feedback operational amplifier with an output connected to bias said drain terminal.
Claim 22
Dependent Claim
49 words
An infrared space surveillance circuit comprising: a sensor; an FET connected to said sensor; means for suppressing drain voltage fluctuations connected to a drain terminal output of said FET wherein said means for suppressing includes a negative feedback operational amplifier with an output connected to bias said drain terminal.
Claim 23
Dependent Claim
26 words
A circuit according to claim 1, wherein a negative input terminal of said operational amplifier stage is connected to a drain output terminal of said FET.
Claim 24
Dependent Claim
49 words
A circuit according to claim 1, wherein said sensor is connected to a gate electrode of said FET, said drain electrode is connected to a negative input of said operational amplifier stage, and a feedback resistor is connected between said negative input and an output of said operational amplifier.
Claim 25
Dependent Claim
59 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; a negative feedback high input impedance operational amplifier stage responsive to said FET; and a constant current source connected to said FET, wherein an output of said operational amplifier is connected to a control input of said constant current source.
Claim 26
Dependent Claim
59 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; a negative feedback high input impedance operational amplifier stage responsive to said FET; and a constant current source connected to said FET, wherein an output of said operational amplifier is connected to a control input of said constant current source.
Claim 27
Dependent Claim
15 words
A circuit according to claim 22 wherein said constant current source is a feedback quadripole.
Claim 28
Dependent Claim
21 words
A circuit according to claim 23 wherein said feedback quadripole is an integrated element for attenuation of said operational amplifier output.
Claim 29
Dependent Claim
25 words
A circuit according to claim 23 wherein an attenuation element of said feedback quadripole exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
Claim 30
Dependent Claim
50 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; a negative feedback high input impedance operational amplifier stage responsive to said FET; and a constant current source connected to said FET, wherein said constant current source is a feedback quadripole.
Claim 31
Dependent Claim
50 words
An infrared space surveillance detector circuit comprising: a sensor; a field effect transistor or FET responsive to said sensor; a negative feedback high input impedance operational amplifier stage responsive to said FET; and a constant current source connected to said FET, wherein said constant current source is a feedback quadripole.
Claim 32
Dependent Claim
21 words
A circuit according to claim 26 wherein said feedback quadripole is an integrated element for attenuation of said operational amplifier output.
Claim 33
Dependent Claim
25 words
A circuit according to claim 27 wherein an attenuation element of said feedback quadripole exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
Claim 34
Dependent Claim
42 words
A space surveillance detector circuit comprising: an infrared radiation sensor; a constant current source four pole network FET stage responsive to said sensor; and a high input impedance operational amplifier network current amplification stage responsive to an output of said FET stage.
Claim 35
Dependent Claim
42 words
A space surveillance detector circuit comprising: an infrared radiation sensor; a constant current source four pole network FET stage responsive to said sensor; and a high input impedance operational amplifier network current amplification stage responsive to an output of said FET stage.
Claim 36
Dependent Claim
24 words
A circuit according to claim 29 wherein said four pole network is an integrating amplifier responsive to an output of said current amplification stage.
Claim 37
Dependent Claim
21 words
A circuit according to claim 30 wherein said integrating amplifier exhibits an attenuation factor controlled proportionally to an overall circuit amplification.
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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) | 1992-05-01 | 1992-10-31 | 1993-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-01 | 1996-10-31 | 1997-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-01 | 2000-10-31 | 2001-05-02 | $7700.00 | Window Closed / Lapsed |