US4039863A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light activated semiconductor switch device
Assignee: Hitachi Ltd
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Filing: 1975-06-26
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Granted: 1977-08-02
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Expires: 1995-06-26
Abstract
Abstract A light activated semiconductor switch device comprising a light activated PNPN switch, an impedance element, a switching element, and a capacitance element. The impedance element and switching element are connected in parallel across the cathode gate and the cathode or across the anode and the anode gate of the light activated PNPN switch, and the switching element is turned on by the current supplied through the capacitance element, so that the device can operate with improved tolerance to dv/dt and high turn-on sensitivity.
Inventors
- 👤 Ichiro Ohhinata
- 👤 Shinzi Okuhara
- 👤 Michio Tokunaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:51
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/16; H03K17/51; H03K17/78; H03K17/79
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
143 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, an anode gate and a cathode gate, an impedance element, a switching means having two terminals in addition to a control terminal for controlling the on-off operation thereof due to a control current supplied thereto and a capacitive element, said impedance element and said two terminals of said switching means being connected in parallel between the cathode gate and the cathode of said light activated PNPN switch, and said control terminal of said switching means being connected through said capacitive element to one of said anode and anode gate of said light activated PNPN switch so as to be turned on by the control current supplied to said control terminal from a current source which is connected to the anode of said light activated PNPN switch.
Claim 2
Dependent Claim
143 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, an anode gate and a cathode gate, an impedance element, a switching means having two terminals in addition to a control terminal for controlling the on-off operation thereof due to a control current supplied thereto and a capacitive element, said impedance element and said two terminals of said switching means being connected in parallel between the cathode gate and the cathode of said light activated PNPN switch, and said control terminal of said switching means being connected through said capacitive element to one of said anode and anode gate of said light activated PNPN switch so as to be turned on by the control current supplied to said control terminal from a current source which is connected to the anode of said light activated PNPN switch.
Claim 3
Dependent Claim
25 words
A light activated semiconductor switch device as claimed in claim 1, wherein said switching means is an NPN transistor having a base, emitter and collector.
Claim 4
Dependent Claim
36 words
A light activated semiconductor switch device as claimed in claim 2, wherein said capacitive element is a diode, connected between the anode gate of said light activated PNPN switch and the base of said NPN transistor.
Claim 5
Dependent Claim
87 words
A light activated semiconductor switch device as claimed in claim 2, wherein said PNPN switch comprises at least a PNP transistor having a base, emitter and collector and wherein said capacitive element is another PNP transistor with a base, emitter and collector and having a small current amplification factor disposed with the emitter and base thereof connected respectively with the emitter and base of the PNP transistor of said PNPN switch and the collector thereof connected with the base of said NPN transistor constituting the switching means.
Claim 6
Dependent Claim
23 words
A light activated semiconductor switch device as claimed in claim 2, wherein another capacitance element is connected in parallel with said impedance element.
Claim 7
Dependent Claim
26 words
A light activated semiconductor switch device as claimed in claim 1, wherein said PNPN switch is composed of a conventional PNPN switch and a photo transistor.
Claim 8
Dependent Claim
143 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, a cathode gate and an anode gate, an impedance element, a switching means having two terminals in addition to a control terminal for controlling the on-off operation thereof due to a control current supplied thereto and a capacitive element, said impedance element and said two terminals of said switching means being connected in parallel between the anode and the anode gate of said light activated PNPN switch, and said control terminal of said switching means being connected through said capacitive element to one of said cathode and cathode gate of said light activated PNPN switch so as to be turned on by the control current supplied to said control terminal from a current source which is connected to the anode of said light activated PNPN switch.
Claim 9
Dependent Claim
143 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, a cathode gate and an anode gate, an impedance element, a switching means having two terminals in addition to a control terminal for controlling the on-off operation thereof due to a control current supplied thereto and a capacitive element, said impedance element and said two terminals of said switching means being connected in parallel between the anode and the anode gate of said light activated PNPN switch, and said control terminal of said switching means being connected through said capacitive element to one of said cathode and cathode gate of said light activated PNPN switch so as to be turned on by the control current supplied to said control terminal from a current source which is connected to the anode of said light activated PNPN switch.
Claim 10
Dependent Claim
19 words
A light activated semiconductor switch device as claimed in claim 7, wherein said switching means is a PNP transistor.
Claim 11
Dependent Claim
36 words
A light activated semiconductor switch device as claimed in claim 8, wherein said capacitive element is a diode, connected between the cathode gate of said light activated PNPN switch and the base of said PNP transistor.
Claim 12
Dependent Claim
23 words
A light activated semiconductor switch device as claimed in claim 7, wherein another capacitive element is connected in parallel with said impedance element.
Claim 13
Dependent Claim
26 words
A light activated semiconductor switch device as claimed in claim 7, wherein said PNPN switch is composed of a conventional PNPN switch and a photo transistor.
Claim 14
Dependent Claim
94 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, an anode gate, a cathode and a cathode gate, an impedance element, a transistor and a capacitive element, said impedance element being connected across a collector and emitter of said transistor, said collector and emitter of said transistor being respectively connected to the cathode gate and the cathode of said light activated PNPN switch, a base of said transistor being connected through said capacitive element to one of the anode and anode gate of said light activated PNPN switch.
Claim 15
Dependent Claim
94 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, an anode gate, a cathode and a cathode gate, an impedance element, a transistor and a capacitive element, said impedance element being connected across a collector and emitter of said transistor, said collector and emitter of said transistor being respectively connected to the cathode gate and the cathode of said light activated PNPN switch, a base of said transistor being connected through said capacitive element to one of the anode and anode gate of said light activated PNPN switch.
Claim 16
Dependent Claim
18 words
A light activated semiconductor switch device as claimed in claim 12, wherein said capacitive element is a capacitor.
Claim 17
Dependent Claim
18 words
A light activated semiconductor switch device as claimed in claim 12, wherein said capacitive element is a diode.
Claim 18
Dependent Claim
23 words
A light activated semiconductor switch device as claimed in claim 12, wherein another capacitive element is connected in parallel with said impedance element.
Claim 19
Dependent Claim
54 words
A light activated semiconductor switch device as claimed in claim 12, wherein said light activated PNPN switch comprises a conventional PNPN switch having an anode, a cathode and a cathode gate, and a photo transistor having an emitter and a collector connected between the cathode and cathode gate, respectively, of said conventional PNPN switch.
Claim 20
Dependent Claim
90 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, a cathode gate and an anode gate, an impedance element, a transistor and a capacitive element, said impedance element being connected across a collector and emitter of said transistor, said emitter and collector being respectively connected to the anode and anode gate of said light activated PNPN switch, a base of said transistor being connected through said cpacitive element to one of the cathode and cathode gate of said light activated PNPN switch.
Claim 21
Dependent Claim
90 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, a cathode gate and an anode gate, an impedance element, a transistor and a capacitive element, said impedance element being connected across a collector and emitter of said transistor, said emitter and collector being respectively connected to the anode and anode gate of said light activated PNPN switch, a base of said transistor being connected through said cpacitive element to one of the cathode and cathode gate of said light activated PNPN switch.
Claim 22
Dependent Claim
18 words
A light activated semiconductor switch device as claimed in claim 17, wherein said capacitive element is a capacitor.
Claim 23
Dependent Claim
18 words
A light activated semiconductor switch device as claimed in claim 17, wherein said capacitive element is a diode.
Claim 24
Dependent Claim
117 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, an anode gate and a cathode gate, an impedance element, a first transistor, a second transistor having a small current amplification factor, said impedance element being connected across a collector and emitter of said first transistor, said collector and emitter of said first transistor being respectively connected to the cathode gate and the cathode of said light activated PNPN switch, an emitter and a base of said second transistor being respectively connected to the anode and the anode gate of said light activated PNPN switch, a collector of said second transistor being connected to the base of said first transistor.
Claim 25
Dependent Claim
117 words
A light activated semiconductor switch device comprising a light activated PNPN switch having an anode, a cathode, an anode gate and a cathode gate, an impedance element, a first transistor, a second transistor having a small current amplification factor, said impedance element being connected across a collector and emitter of said first transistor, said collector and emitter of said first transistor being respectively connected to the cathode gate and the cathode of said light activated PNPN switch, an emitter and a base of said second transistor being respectively connected to the anode and the anode gate of said light activated PNPN switch, a collector of said second transistor being connected to the base of said first transistor.
Claim 26
Dependent Claim
23 words
A light activated semiconductor switch device as claimed in claim 20, wherein a capacitive element is connected in parallel with said impedance element.
Claim 27
Dependent Claim
53 words
A light activated semiconductor switch device as claimed in claim 20, wherein said light activated PNPN switch comprises a conventional PNPN switch having an anode, a cathode and a cathode gate, and a phototransistor having an emitter and a collector connected between the cathode and cathode gate, respectively, of said conventional PNPN switch.
References Cited (Backward Citations)
US3714443A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-01 | 1981-01-31 | 1981-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-01 | 1985-01-31 | 1985-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-01 | 1989-01-31 | 1989-08-02 | $7700.00 | Window Closed / Lapsed |