US3621290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rf-controlled solid-state switch
Assignee: National Aeronautics and Space Administration
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Filing: 1969-10-09
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Granted: 1971-11-16
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Expires: 1989-10-09
Abstract
Abstract An electronic element, capable of presenting either a high impedance or a low impedance between a power source and an instrument, is switched from its high impedance to its low impedance state by turning on both active elements of a complementary bistable multivibrator. By momentarily shortcircuiting one of the two active elements of the complementary bistable multivibrator, thereby driving its two active elements from the on to the off state, the electronic element is switched back from its low impedance to its high impedance state. When off, this circuit consumes essentially zero standby power. Alternative-switching circuits use symmetrical bistable multivibrators, activated by amplified and rectified transmitted pulses, to switch a gating element from its high impedance to its low impedance state, and vice versa.
Inventors
- 👤 Thomas B Fryer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:04
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/12; A; A61; A61B; A61B5/00; A61B5/0002; H; H03; H03K; H03K17/00; H03K17/30; Y; Y10; Y10S; Y10S128/00; Y10S128/903
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
219 words
A bistable switch which comprises a gating element capable of providing either a high impedance or a low impedance path between a power supply and a load; means for switching said gating element, said switching means being responsive to a first signal for switching said gating element to said low impedance state, said switching means being responsive to a second signal for switching said gating element to said high impedance state; said switching means comprising means for detecting the receipt of said first and second signals, means for rectifying said first and second detected signals to produce the envelopes of said first and second signals, means for amplifying said envelopes to produce first and second intermediate signals, respectively, from said first and second signals, a complementary bistable multivibrator containing first and second active elements, said multivibrator being coupled to said gating element, both of said elements being normally off and said gating element being normally in its high impedance state, a first diode connected in series with a first capacitor, said series-connected diode and capacitor being coupled to said first active element in said complementary bistable multivibrator and said first diode, normally backbiased, being forward-biased by said first intermediate signal, thereby turning on said first and second active elements and switching said gating element to its low impedance state.
Claim 2
Dependent Claim
219 words
A bistable switch which comprises a gating element capable of providing either a high impedance or a low impedance path between a power supply and a load; means for switching said gating element, said switching means being responsive to a first signal for switching said gating element to said low impedance state, said switching means being responsive to a second signal for switching said gating element to said high impedance state; said switching means comprising means for detecting the receipt of said first and second signals, means for rectifying said first and second detected signals to produce the envelopes of said first and second signals, means for amplifying said envelopes to produce first and second intermediate signals, respectively, from said first and second signals, a complementary bistable multivibrator containing first and second active elements, said multivibrator being coupled to said gating element, both of said elements being normally off and said gating element being normally in its high impedance state, a first diode connected in series with a first capacitor, said series-connected diode and capacitor being coupled to said first active element in said complementary bistable multivibrator and said first diode, normally backbiased, being forward-biased by said first intermediate signal, thereby turning on said first and second active elements and switching said gating element to its low impedance state.
Claim 3
Dependent Claim
120 words
Structure as in claim 1 wherein said switching means further comprises: a second diode connected in series with a second capacitor; a third active element connected to said second capacitor, said second diode, normally back-biased, being forward-biased by said second intermediate signal, so that said second intermediate signal passes through said second diode and said second capacitor to turn on said third active element, said third active element being connected so as to short circuit said first active element on receipt of said second intermediate signal, thereby driving said first active element and said second active element from the on state to the off state and thus switching said gating element from its low impedance to its high impedance state.
Claim 4
Dependent Claim
186 words
Structure as in claim 2 wherein said first and second active elements comprise: a first conductivity-type transistor and a second opposite conductivity-type transistor, respectively, both transistors containing a base lead, an emitter lead, and a collector lead, the base of said first conductivity-type transistor being coupled to the collector of said second opposite conductivity-type transistor by a first parallel combination of a resistor and a capacitor, the base of said second opposite conductivity-type transistor being coupled to the collector of said first conductivity-type transistor by a second parallel combination of a resistor and a capacitor, said first parallel combination being connected in series with a resistor between the collector of said second opposite conductivity-type transistor and ground, said second parallel combination being connected in series with a resistor between the collector of said first conductivity-type transistor and a power supply, said emitter lead of said first conductivity-type transistor being grounded, said emitter lead of said second opposite conductivity-type transistor being connected to said power supply, and said base lead and said emitter lead of said first conductivity-type transistor being additionally connected to said third active element.
Claim 5
Dependent Claim
46 words
Structure as in claim 3 in which said second diode is connected to remain back-biased during the receipt of said first signal by said detecting means while said first diode is connected to remain back-biased during the receipt of said second signal by said detecting means.
Claim 6
Dependent Claim
72 words
Structure as in claim 4 wherein a resistor couples said gating element to said collector of said first conductivity-type transistor. 6 Structure as in claim 5 in which said gating element comprises a first transistor the base of which is connected through said resistor to said collector of said first conductivity-type transistor, the emitter of which is connected to a power supply, and the collector of which is connected to a load.
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) | 1974-11-15 | 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 |