US5150028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two Zener diode one power supply fast turn off
Assignee: Sundstrand Corp
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Filing: 1990-10-31
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Granted: 1992-09-22
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Expires: 2010-10-31
Abstract
Abstract The drive circuit for controlling conductivity of a load switch (12) for controlling current flow through an electrical load (14) in accordance with the invention includes a DC source (20) having a positive terminal and a negative terminal; first and second voltage limiting devices (100) and (102) coupled together at a junction point (108) and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal and a control circuit (24 and 28) causing current flow through only one of the voltage limiting devices with a reverse current breakdown which reverse biases the control electrode of the load switch causing the load switch to turn off.
Inventors
- 👤 Rasappa Palaniappan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:38
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/04; H03K17/041; H03K17/0412; H03K17/04126
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
240 words
A drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load comprising: a DC source having a positive terminal and a negative terminal; a first switch and a second switch each having a control electrode and first and second power electrodes, the first and second switches having the first power electrodes respectively coupled to the positive and negative terminals and the second power electrodes coupled to a junction point coupled to a control electrode of the load switch, conduction of the first switch causing the load switch to turn on by applying a control signal to the control electrode of the load switch and conduction of the second switch causing the load switch to be turned off by applying a control signal to the control electrode of the load switch; first and second voltage limiting devices coupled together at a point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and wherein conduction of the second switch causes current flow through only one of the voltage limiting devices which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to be turned off.
Claim 2
Dependent Claim
240 words
A drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load comprising: a DC source having a positive terminal and a negative terminal; a first switch and a second switch each having a control electrode and first and second power electrodes, the first and second switches having the first power electrodes respectively coupled to the positive and negative terminals and the second power electrodes coupled to a junction point coupled to a control electrode of the load switch, conduction of the first switch causing the load switch to turn on by applying a control signal to the control electrode of the load switch and conduction of the second switch causing the load switch to be turned off by applying a control signal to the control electrode of the load switch; first and second voltage limiting devices coupled together at a point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and wherein conduction of the second switch causes current flow through only one of the voltage limiting devices which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to be turned off.
Claim 3
Dependent Claim
16 words
A drive circuit in accordance with claim 1 wherein: the load switch is a semiconductor switch.
Claim 4
Dependent Claim
15 words
A drive circuit in accordance with claim 2 wherein: the load switch is a transistor.
Claim 5
Dependent Claim
16 words
A drive circuit in accordance with claim 3 wherein: the load switch is a bipolar transistor.
Claim 6
Dependent Claim
44 words
A drive circuit in accordance with claim 1 wherein: the first and second switches are in a series circuit; and the voltage limiting devices are in a series circuit which is connected in parallel to a series connection of the first and second switches.
Claim 7
Dependent Claim
73 words
A drive circuit in accordance with claim 5 wherein: each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 8
Dependent Claim
18 words
A drive circuit in accordance with claim 6 wherein: the voltage limiting devices comprise series connected Zener diodes.
Claim 9
Dependent Claim
51 words
A drive circuit in accordance with claim 7 wherein: a current flow through only one of the voltage limiting devices flows between the power electrode of the load switch, the control electrode of the load switch and an impedance coupled to the second switch and to the one voltage limiting device.
Claim 10
Dependent Claim
44 words
A drive circuit in accordance with claim 2 wherein: the first and second switches are in a series circuit; and the voltage limiting devices are in a series circuit which is connected in parallel to a series connection of the first and second switches.
Claim 11
Dependent Claim
73 words
A drive circuit in accordance with claim 9 wherein: each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 12
Dependent Claim
18 words
A drive circuit in accordance with claim 10 wherein: the voltage limiting devices comprise series connected Zener diodes.
Claim 13
Dependent Claim
50 words
A drive circuit in accordance with claim 11 wherein: current flow through only one of the voltage limiting devices flows between the power electrode of the load switch, the control electrode of the load switch and an impedance coupled to the second switch and to the one voltage limiting device.
Claim 14
Dependent Claim
44 words
A drive circuit in accordance with claim 3 wherein: the first and second switches are in a series circuit; and the voltage limiting devices are in a series circuit which is connected in parallel to a series circuit of the first and second switches.
Claim 15
Dependent Claim
73 words
A drive circuit in accordance with claim 13 wherein: each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 16
Dependent Claim
18 words
A drive circuit in accordance with claim 14 wherein: the voltage limiting devices comprise series connected Zener diodes.
Claim 17
Dependent Claim
51 words
A drive circuit in accordance with claim 15 wherein: a current flow through only one of the voltage limiting devices flows between the power electrode of the load switch, the control electrode of the load switch and an impedance coupled to the second switch and to the one voltage limiting device.
Claim 18
Dependent Claim
44 words
A drive circuit in accordance with claim 4 wherein: the first and second switches are in a series circuit; and the voltage limiting devices are in a series circuit which is connected in parallel to a series circuit of the first and second switches.
Claim 19
Dependent Claim
73 words
A drive circuit in accordance with claim 17 wherein: each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 20
Dependent Claim
18 words
A drive circuit in accordance with claim 18 wherein: the voltage limiting devices comprise series connected Zener diodes.
Claim 21
Dependent Claim
51 words
A drive circuit in accordance with claim 19 wherein: a current flow through only one of the voltage limiting devices flows between the power electrode of the load switch, the control electrode of the load switch and an impedance coupled to the second switch and to the one voltage limiting device.
Claim 22
Dependent Claim
137 words
In a drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load, and improvement comprising: a DC source having a positive terminal and a negative terminal; first and second voltage limiting devices coupled together at a point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and a control circuit causing current flow through only one of the voltage limiting devices with a reverse current breakdown which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to turn off.
Claim 23
Dependent Claim
137 words
In a drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load, and improvement comprising: a DC source having a positive terminal and a negative terminal; first and second voltage limiting devices coupled together at a point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and a control circuit causing current flow through only one of the voltage limiting devices with a reverse current breakdown which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to turn off.
Claim 24
Dependent Claim
56 words
A drive circuit in accordance with claim 21 wherein the control circuit comprises: a switch coupled between the power electrode of the load switch and the DC source which when conductive permits current flow between the DC source, the switch and the power electrode to reverse bias the load switch to turn off the load switch.
Claim 25
Dependent Claim
203 words
In a drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load, an improvement comprising: a DC source having a positive terminal and a negative terminal; first and second voltage limiting devices coupled together at a junction point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and a control circuit causing current flow through only one of the voltage limiting devices with a reverse current breakdown which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to turn off; and each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 26
Dependent Claim
203 words
In a drive circuit for controlling conductivity of a load switch for controlling current flow through an electrical load, an improvement comprising: a DC source having a positive terminal and a negative terminal; first and second voltage limiting devices coupled together at a junction point coupled to a power electrode of the load switch and an electrode of the first voltage limiting device being coupled to the positive terminal and an electrode of the second voltage limiting device being coupled to the negative terminal; and a control circuit causing current flow through only one of the voltage limiting devices with a reverse current breakdown which reverse biases the control electrode of the load switch in response to an electrical potential between the control and the power electrode of the load switch causing the load switch to turn off; and each voltage limiting device has a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current magnitude and a sum of the voltage limits of the voltage limiting devices is greater than the DC potential so that only one of the voltage limiting devices limits voltage independent of current magnitude when the second switch is conductive.
Claim 27
Dependent Claim
33 words
A drive circuit in accordance with claim 23 wherein: the voltage limiting devices comprise series connected Zener diodes which are connected in parallel to a series connection of the first and second switches.
Claim 28
Independent Claim
150 words
A method of controlling conductivity of a load switch controlling current flow through an electrical load comprising: applying a control signal to a control terminal of the load switch to turn on the load switch; and applying a control signal to the control terminal of the load switch to turn off the load switch by causing current flow through only one of first and second connected voltage limiting devices which is operating in a reverse current breakdown and between a control electrode of the load switch and each voltage limiting device having a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current and a sum of the voltage limits of the voltage limiting devices is greater than a DC potential coupled to the voltage limiting devices so that only one of the voltage limiting devices limits voltage independent of current magnitude.
Claim 29
Independent Claim
150 words
A method of controlling conductivity of a load switch controlling current flow through an electrical load comprising: applying a control signal to a control terminal of the load switch to turn on the load switch; and applying a control signal to the control terminal of the load switch to turn off the load switch by causing current flow through only one of first and second connected voltage limiting devices which is operating in a reverse current breakdown and between a control electrode of the load switch and each voltage limiting device having a reverse current breakdown which limits a voltage which is dropped across the voltage limiting device independent of current and a sum of the voltage limits of the voltage limiting devices is greater than a DC potential coupled to the voltage limiting devices so that only one of the voltage limiting devices limits voltage independent of current magnitude.
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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) | 1995-09-22 | 1996-03-23 | 1996-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-22 | 2000-03-23 | 2000-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-22 | 2004-03-23 | 2004-09-22 | $7700.00 | Window Closed / Lapsed |