OVERVOLTAGE PROTECTION DEVICE

• US 20140293493A1
• Filed: 03/28/2014
• Published: 10/02/2014
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics Tours SAS (STMicroelectronics NV)
• Inventors: Heurtier, Jrme, Florence, Arnaud, Bougrine, Guillaume
• Granted Patent: US 9,461,466 B2
• Time in Patent Office: Days
• US Class Current: 361/91.5
• CPC Class Codes: H02H 3/20 responsive to excess voltage
• CPC Class Codes: H02H 7/26 Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured locating faults in cables G01R31/08
• CPC Class Codes: H02H 9/04 responsive to excess voltage lightning arrestors H01C7/12, H01C8/04, H01G9/18, H01T
• CPC Class Codes: H02H 9/041 using a short-circuiting device
• CPC Class Codes: H02H 9/042 comprising means to limit the absorbed power or indicate damaged over-voltage protection device
• CPC Class Codes: H02H 9/043 Protection of over-voltage protection device by short-circuiting

Abstract

An overvoltage protection device capable of protecting a power supply line and including in parallel a break-over diode, a controlled switch, and a circuit for controlling the switch.

Claims

1. An overvoltage protection device capable of protecting a power supply line, comprising:

a diode component including a break-over diode,

a controlled switch in parallel with the diode component, and

a circuit coupled to the break-over diode and configured to control the switch.

2. The overvoltage protection device of claim 1, wherein the diode component includes an avalanche diode in series with the break-over diode and having a breakdown voltage at least ten times lower than a break-over voltage of the break-over diode.

3. The overvoltage protection device of claim 1, wherein the diode component has a breakdown voltage ranging between 50 and 1,000 volts.

4. The protection component of claim 1, wherein the control circuit comprises an overvoltage detector configured to detect an overvoltage and the control circuit is configured to turn on the switch for a time period in response to the overvoltage detector detecting the overvoltage, and turn off the switch when the time period elapses.

5. The protection component of claim 1, wherein the control circuit comprises a voltage detector configured to detect a voltage across the diode component and the control circuit is configured to turn on the switch in response to the voltage detector detecting that the voltage across the diode is within a given range, corresponding to a value of the voltage across the diode component when said diode component is shorted, and turn off the switch after a determined time.

6. The protection component of claim 1, wherein the control circuit comprises:

a first comparator configured to compare a voltage on an anode of the diode component to a reference voltage;

a second comparator configured to compare the voltage on the anode with a threshold substantially corresponding to a voltage across the diode when shorted;

an AND gate having first and second inputs respectively coupled to outputs of the first and second comparators; and

a buffer amplifier coupled between an output of the AND gate and a control terminal of the switch.

12. The apparatus of claim 6, wherein the control circuit comprises:

a first comparator configured to compare a voltage on an anode of the diode component to a reference voltage;

a second comparator configured to compare the voltage on the anode with a threshold substantially corresponding to a voltage across the diode when shorted;

an AND gate having first and second inputs respectively coupled to outputs of the first and second comparators; and

a buffer amplifier coupled between an output of the AND gate and a control terminal of the switch.

7. An apparatus, comprising:

a power supply line; and

an overvoltage protection device configured to protect the power supply line, the overvoltage protection device including;

a diode component including a break-over diode coupled to the power supply line,

a controlled switch in parallel with the diode component, and

a circuit coupled to the break-over diode and configured to control the switch.

8. The apparatus of claim 7, wherein the diode component includes an avalanche diode in series with the break-over diode and having a breakdown voltage at least ten times lower than a break-over voltage of the break-over diode.

9. The apparatus of claim 7, wherein the diode component has a breakdown voltage ranging between 50 and 1,000 volts.

10. The apparatus of claim 7, wherein the control circuit comprises an overvoltage detector configured to detect an overvoltage and the control circuit is configured to turn on the switch for a time period in response to the overvoltage detector detecting the overvoltage, and turn off the switch when the time period elapses.

11. The apparatus of claim 7, wherein the control circuit comprises a voltage detector configured to detect a voltage across the diode component and the control circuit is configured to turn on the switch in response to the voltage detector detecting that the voltage across the diode is within a given range, corresponding to a value of the voltage across the diode component when said diode component is shorted, and turn off the switch after a determined time.

13. An apparatus, comprising:

an electrical component configured to be coupled to a power supply line; and

an overvoltage protection device configured to protect the electrical component from an overvoltage from the power supply line, the overvoltage protection device including;

a diode component including a break-over diode,

a controlled switch in parallel with the diode component, and

a circuit coupled to the break-over diode and configured to control the switch.

14. The apparatus of claim 13, wherein the diode component includes an avalanche diode in series with the break-over diode and having a breakdown voltage at least ten times lower than a break-over voltage of the break-over diode.

15. The apparatus of claim 13, wherein the diode component has a breakdown voltage ranging between 50 and 1,000 volts.

16. The apparatus of claim 13, wherein the control circuit comprises an overvoltage detector configured to detect an overvoltage and the control circuit is configured to turn on the switch for a time period in response to the overvoltage detector detecting the overvoltage, and turn off the switch when the time period elapses.

17. The apparatus of claim 13, wherein the control circuit comprises a voltage detector configured to detect a voltage across the diode component and the control circuit is configured to turn on the switch in response to the voltage detector detecting that the voltage across the diode is within a given range, corresponding to a value of the voltage across the diode component when said diode component is shorted, and turn off the switch after a determined time.

18. The apparatus of claim 13, wherein the control circuit comprises:

a first comparator configured to compare a voltage on an anode of the diode component to a reference voltage;

a second comparator configured to compare the voltage on the anode with a threshold substantially corresponding to a voltage across the diode when shorted;

an AND gate having first and second inputs respectively coupled to outputs of the first and second comparators; and

a buffer amplifier coupled between an output of the AND gate and a control terminal of the switch.