Burnout protection switch

• US 20070127179A1
• Filed: 12/05/2005
• Published: 06/07/2007
• Est. Priority Date: 12/05/2005
• Status: Abandoned Application

• Current Assignee: Intermatic Incorporated (Wpa Participações e Serviços SA)
• Original Assignee: Intermatic Incorporated (Wpa Participações e Serviços SA)
• Inventors: Reckamp, Steven, Ludjin, William
• Application Number:
  US11/294,353
• Publication Number:
  US 20070127179A1
• Time in Patent Office: Days
• US Class Current: 361/93.100
• CPC Class Codes: H03K 17/0822 in field-effect transistor switches
• CPC Class Codes: H03K 17/284 in field effect transistor switches
• CPC Class Codes: H03K 2217/94089 Wireless transmission

Abstract

A switch connecting a power source and a load may protect its internal circuitry from a current surge. The switch may include a first element, control logic, and a detector. The first element may provide a current path to the load. The detector may detect or measure the voltage across and/or the current flowing through the first element. Based on the measured or detected voltage and/or current, the control logic may remove a control signal provided to the first element, causing the first element to turn off.

Claims

1. A switch for connecting a power source to a load, comprising:

a first element configured to connect the power source to the load;

a control logic connected with the first element, where the control logic controls a switching of the first element with a control signal; and

a detector connected with the control logic, where the detector detects at least one of a voltage across or a current flowing through the first element and sends a value to the control logic based on the detected voltage or current, where the control logic controls the first element to break a current path if the voltage across or the current through the first element exceeds a determined amount.

2. The switch of claim 1, further comprising a second element coupled to the first element;

where the detector detects at least one of a voltage across or a current flowing through the first or second elements and sends a value to the control logic based on the detected voltage or current, where the control logic controls the first or second element to break a current path if the voltage across or the current flowing through the first or second element exceeds a determined amount.

3. The switch of claim 2, where the detector is further configured to send a value to the control logic when the detected voltage across or current flowing through the first or second elements exceeds a determined amount for a determined amount of time.

4. The switch of claim 3, where the control logic is configured to remove the control signal after receiving the value from the detector.

5. The switch of claim 4, where the first and second elements break a current path at approximately the same time the control signal is removed.

6. The light switch of claim 5, where the detector is configured to wait a determined period of time after sending the value to the control logic, and then directs the control logic to restore the control signal to the first and second elements.

7. The light switch of claim 6, where the first and second elements are MOSFET devices.

8. A circuit, comprising:

a first element configured to receive a current flowing through a load;

a control logic that controls the first element by supplying a control signal; and

a detector coupled to the first element that detects a burnout condition across the first element;

where the first element breaks a current path once a burnout condition is detected.

9. The circuit of claim 8, further comprising a second element coupled to the first element;

where the detector further detects a burnout condition across the second element and the second element breaks a current path once a burnout condition is detected.

10. The circuit of claim 9, where the first or second element breaks a current path where the detected voltage exceeds a determined amount.

11. The circuit of claim 10, where the first and second elements break a current path at approximately the same time the control signal is removed.

12. The circuit of claim 11, where the detector causes the control logic to suspend the control signal.

13. The circuit of claim 12, where the control logic is configured to restore the control signal after a determined amount of time.

14. The circuit of claim 13, where the first and second elements are MOSFET devices.

15. A method of protecting a circuit from a current surge, comprising:

engaging a first element configured to connect a power source to a load;

detecting a burnout condition across the first element; and

disengaging the first switch once a burnout condition has been detected;

where the first element breaks a current path once it is disengaged.

16. The method of claim 15, further comprising engaging a second element coupled to the first element;

where the second element is engaged when the first element is engaged.

17. The method of claim 16, where the act of engaging the first and second elements comprises supplying the first and second element with a control signal from a control logic.

18. The method of claim 17, where the act of detecting a burnout condition comprises determining that the voltage across the first or second element exceeds a determined amount.

19. The method of claim 18, where the act of detecting a burnout condition comprises determined that the voltage across the first or second element exceeds a determined amount for a determined amount of time.

20. The method of claim 19, where the act of disengaging the first and second elements comprises preventing each of the elements from receiving the control signal.

21. The method of claim 20, further comprising waiting a determined period of time after disengaging the first and second elements before reengaging the first and second elements.