Patent US3614472A successfully refreshed from Google Patents.
US3614472A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switching device
Assignee: US Philips Corp
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Filing: 1969-06-03
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Granted: 1971-10-19
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Expires: 1989-06-03
Abstract
Abstract A switching circuit comprising a resistance bridge and a signal transmission path including a pair of switching transistors of opposite conductivity connected in parallel across one diagonal of the bridge to form complementary signal paths. A source of DC voltage is connected to the other diagonal of the bridge. The base electrodes of the switching transistors are connected to opposite terminals of the DC source, each via a diode and a basekeying transistor in series. A common control transistor provides a means for simultaneously blocking and unblocking the basekeying transistors whereby the switching transistors are simultaneously blocked or unblocked.
Inventors
- 👤 Nico J Kloppenborg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:30
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/60; H03K17/10; H03K17/68
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
121 words
A transistor-swtiching circuit comprising a resistance bridge, a signal transmission path formed by the emitter/collector paths of at least one pair of switching transistors of opposite conductivity type forming two parallel and complementary paths across one diagonal of the resistance bridge, means connecting the remaining bridge diagonal across the terminals of a source of DC potential, means connecting the respective base electrodes of the switching transistors to opposite terminals of the source, each via the collector/emitter path of an associated base-keying transistor, a unidirectional current-conducting device serially connected between the base electrode of each switching transistor and its associated basekeying transistor, means being provided for simultaneously blocking and unblocking the base-keying transistors whereby the switching transistors are simultaneously blocked or unblocked.
Claim 2
Dependent Claim
121 words
A transistor-swtiching circuit comprising a resistance bridge, a signal transmission path formed by the emitter/collector paths of at least one pair of switching transistors of opposite conductivity type forming two parallel and complementary paths across one diagonal of the resistance bridge, means connecting the remaining bridge diagonal across the terminals of a source of DC potential, means connecting the respective base electrodes of the switching transistors to opposite terminals of the source, each via the collector/emitter path of an associated base-keying transistor, a unidirectional current-conducting device serially connected between the base electrode of each switching transistor and its associated basekeying transistor, means being provided for simultaneously blocking and unblocking the base-keying transistors whereby the switching transistors are simultaneously blocked or unblocked.
Claim 3
Dependent Claim
64 words
A circuit as claimed in claim 1, characterized in that said signal transmission path is formed by the emitter/collector paths of at least two pairs of switching transistors, the transistors of each pair being of opposite conductivity type, the emitter/collector paths of the transistors of like conductivity type being serially connected thereby forming two complementary paths across said one diagonal of said resistance bridge.
Claim 4
Dependent Claim
115 words
A circuit as claimed in claim 2, characterized in that the base electrode of each base-keying transistor associated with a switching transistor of the one conductivity type is connected to the collector electrode of a common control transistor and the base electrode of each base-keying transistor associated with a switching transistor of the opposite conductivity type is connected to the emitter electrode of said control transistor, the collector and emitter electrodes of the control transistor being respectively connected via a collector resistance and an emitter resistance to terminals of said source of DC potential, and means being provided for blocking and unblocking the control transistor to effect simultaneously blocking or unblocking of the base-keying transistors.
Claim 5
Dependent Claim
125 words
A circuit as claimed in claim 1 further comprising a common control transistor, means connecting the base electrode of a base-keying transistor associated with a switching transistor of the one conductivity type to the collector electrode of said control transistor and the base electrode of a base-keying transistor associated with a switching transistor of the opposite conductivity type to the emitter electrode of said control transistor, first and second resistors, means respectively connecting the collector and emitter electrodes of the control transistor to the terminals of said DC source via said first and second resistors, respectively, and means coupled to the base electrode of the control transistor for blocking and unblocking the control transistor thereby to simultaneously effect blocking or unblocking of the base-keying transistors.
Claim 6
Dependent Claim
19 words
A circuit as claimed in claim 4 wherein said first and second resistors are of substantially equal resistance value.
Claim 7
Dependent Claim
38 words
A circuit as claimed in claim 4 wherein the series resistors in one leg of the bridge are substantially equal in value and the series resistors in the other leg of the bridge are substantially equal in value.
Claim 8
Dependent Claim
25 words
A circuit as claimed in claim 4 wherein said unidirectional devices comprise semiconductor diodes connected with like polarity between the terminals of the DC source.
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) | 1974-10-18 | 1975-04-19 | 1975-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-18 | 1979-04-19 | 1979-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-18 | 1983-04-19 | 1983-10-19 | $7700.00 | Window Closed / Lapsed |