US4520277A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High gain thyristor switching circuit
Assignee: Texas Instruments Inc
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Filing: 1982-05-10
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Granted: 1985-05-28
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Expires: 2002-05-10
Abstract
Abstract A three terminal power switch utilizing a lateral thyristor switching circuit is disclosed which exhibits very high gain for both turn-on and turn-off. The gate turn-off capability of the lateral thyristor is accomplished utilizing a secondary shunting thyristor to pull current out of the gate in response to the turn-off signal. The output thyristor is designed to maximize its turn-off gain, and the drive thyristor is designed for optimum forward conduction characteristics; the output thyristor carries approximately ten times the current of the drive thyristor, in one embodiment.
Inventors
- 👤 Larry A. Hahn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:17
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/60; H03; H03K; H03K17/00; H03K17/04; H03K17/0403
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
135 words
A switch circuit having substantially equal gain for both turn-on and turn-off amplification for completing a current path from a source of power, through a load, to ground, comprising: a. a first thyristor, having an anode connected to said load, a cathode, and a gate; b. at least one diode connected in series between an input signal terminal and the gate of said first thyristor; c. a second thyristor, having an anode connected to the gate terminal of said first thyristor, a cathode connected to ground, and a gate connected to receive an input signal on said input signal terminal; and d. a junction diode connected as a load in series between the cathode of said first thyristor and ground to compensate for a voltage differential between the gate of said first thyristor and ground.
Claim 2
Dependent Claim
135 words
A switch circuit having substantially equal gain for both turn-on and turn-off amplification for completing a current path from a source of power, through a load, to ground, comprising: a. a first thyristor, having an anode connected to said load, a cathode, and a gate; b. at least one diode connected in series between an input signal terminal and the gate of said first thyristor; c. a second thyristor, having an anode connected to the gate terminal of said first thyristor, a cathode connected to ground, and a gate connected to receive an input signal on said input signal terminal; and d. a junction diode connected as a load in series between the cathode of said first thyristor and ground to compensate for a voltage differential between the gate of said first thyristor and ground.
Claim 3
Dependent Claim
60 words
The switch circuit of claim 1 further comprising a first resistor in series with said input signal terminal and said at least one diode for controlling said input signal, and a second resistor connected between the gate of said first thyristor and ground for controlling the potential on the gate of said first thyristor with respect to the input signal.
Claim 4
Dependent Claim
37 words
A circuit as in claim 1 wherein the inverse of the turn-off gain of said first thyristor multiplied by the current carrying capacity of said first thyristor substantially approximates the current carrying capacity of said second thyristor.
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) | 1988-05-27 | 1988-11-26 | 1989-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-27 | 1992-11-26 | 1993-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-27 | 1996-11-26 | 1997-05-28 | $7700.00 | Window Closed / Lapsed |