US3694670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Easily switched silicon controlled rectifier
Assignee: Individual
•
Filing: 1971-10-26
•
Granted: 1972-09-26
•
Expires: 1991-10-26
Abstract
Abstract A combination of transistors, which can be integrally formed with an SCR is used to effect a turn-off. The magnitude of the turn-off pulse is less than that required to turn it on. When the entire circuit is self contained, only four leads to the device are required. Two of the leads handle the load current in the typical well known manner. The SCR turn-on is effected by a pulse applied to the gate through a third lead. A fourth lead is provided to turn the SCR off by causing an anode to cathode short across the SCR. This short is controlled by two transistors connected in an ''''inverted darlington'''' configuration.
Inventors
- 👤 Joseph M Marzolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:36
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/73; H10; H10D; H10D84/00; H10D84/60; Y; Y10; Y10S; Y10S148/00; Y10S148/037; Y10S148/085
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
A silicon controlled rectifier circuit for aiding turn-off comprising: a silicon controlled rectifier having an anode, a cathode, and a gate for turning the rectifier on upon application of an electrical pulse thereto; means connected between said anode and said cathode for turning the silicon controlled rectifier off, said means for turning said rectifier off being operative upon application of an electrical pulse having a polarity identical to the pulse applied on said gate to turning said rectifier on and of less voltage magnitude than the voltage magnitude required in the pulse applied on said gate for turning said rectifier on.
Claim 2
Dependent Claim
101 words
A silicon controlled rectifier circuit for aiding turn-off comprising: a silicon controlled rectifier having an anode, a cathode, and a gate for turning the rectifier on upon application of an electrical pulse thereto; means connected between said anode and said cathode for turning the silicon controlled rectifier off, said means for turning said rectifier off being operative upon application of an electrical pulse having a polarity identical to the pulse applied on said gate to turning said rectifier on and of less voltage magnitude than the voltage magnitude required in the pulse applied on said gate for turning said rectifier on.
Claim 3
Dependent Claim
31 words
The silicon controlled rectifier circuit as claimed in claim 1 wherein said silicon controlled rectifier and said means for turning said silicon controlled rectifier off are deposited on a common substrate.
Claim 4
Dependent Claim
135 words
A silicon controlled rectifier having an anode, a cathode, and a gate for turning the rectifier on upon application of an electrical pulse thereto; said anode and said cathode being coupled in series with a load and a voltage source, the improvement comprising: a PNP transistor having an emitter, a base, and a collector, said emitter connected to said anode, said collector connected to said cathode; and a NPN transistor having a base, a collector, and an emitter, the collector of said NPN transistor connected to the base of said PNP transistor, the emitter of said NPN transistor connected to said cathode, said gate of the silicon controlled rectifier and said base of said NPN transistor being connectable to means for applying a pulse thereto, respectively for turning the silicon controlled rectifier on and off.
Claim 5
Dependent Claim
135 words
A silicon controlled rectifier having an anode, a cathode, and a gate for turning the rectifier on upon application of an electrical pulse thereto; said anode and said cathode being coupled in series with a load and a voltage source, the improvement comprising: a PNP transistor having an emitter, a base, and a collector, said emitter connected to said anode, said collector connected to said cathode; and a NPN transistor having a base, a collector, and an emitter, the collector of said NPN transistor connected to the base of said PNP transistor, the emitter of said NPN transistor connected to said cathode, said gate of the silicon controlled rectifier and said base of said NPN transistor being connectable to means for applying a pulse thereto, respectively for turning the silicon controlled rectifier on and off.
Claim 6
Dependent Claim
21 words
The device as claimed in claim 3 wherein said silicon controlled rectifier and said NPN and PNP transistors are discrete components.
Claim 7
Dependent Claim
24 words
The device as claimed in claim 3 wherein said silicon controlled rectifier and said PNP and NPN transistors are deposited on a common substrate.
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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) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |