Switch Device

Patent metadata

Field	Value
Publication number	US-2016313402-A1
Application number	US-201514694242-A
Country	US
Kind code	A1
Filing date	Apr 23, 2015
Priority date	Apr 23, 2015
Publication date	Oct 27, 2016
Grant date	—

Abstract

According to an embodiment of a switch device, the switch device includes a first switch, a second switch and an evaluation circuit. The evaluation circuit is configured to evaluate a temporal behavior of a node between the first switch and the second switch to detect a possible fault condition of at least one of the first switch or the second switch. A corresponding fault detection method for a switch device having a first switch and a second switch is also provided.

First claim

What is claimed is:

1 . A switch device, comprising:
a first switch; a second switch; and an evaluation circuit configured to evaluate a temporal behavior of a node between the first switch and the second switch to detect a possible fault condition of at least one of the first switch or the second switch.

2 . The switch device of claim 1 , further comprising a control circuit configured to, when the switch device is to be closed, first close the first switch and then close the second switch, and, when the switch device is to be opened, first open the second switch and then open the first switch.

3 . The switch device of claim 2 , wherein the evaluation circuit is configured to detect a possible fault condition of the first switch.

4 . The switch device of claim 1 , wherein the first switch comprises a semiconductor switch.

5 . The switch device of claim 4 , wherein the second switch comprises one of a semiconductor switch and a mechanical switch.

6 . The switch device of claim 1 , wherein the first switch comprises a mechanical switch, and wherein the second switch comprises a mechanical switch.

7 . The switch device of claim 1 , further comprising terminals configured to be coupled with a load between the first switch and the second switch.

8 . The switch device of claim 1 , wherein the evaluation circuit is configured to monitor the temporal behavior when starting from a state in which the first and second switches are closed, the first switch is then opened followed by an opening of the second switch.

9 . The switch device of claim 1 , further comprising a circuit path configured to selectively charge the node to a first voltage, wherein the evaluation circuit is configured to monitor a change of a voltage at the node from the first voltage to a second voltage.

10 . The switch device of claim 9 , wherein the path comprises a resistor having a higher resistance than a resistance of the first switch in a closed state.

11 . The switch device of claim 1 , further comprising a capacitance coupled between the node and a terminal of the first switch.

12 . The switch device of claim 1 , wherein the evaluation circuit comprises a measurement transistor, wherein a control terminal of the measurement transistor is coupled to the node.

13 . The switch device of claim 12 , wherein a terminal of the transistor is coupled to a timer.

14 . A fault detection method for a switch device having a first switch and a second switch, the method comprising:
evaluating a temporal behavior of a node between the first and second switches; and determining a possible fault condition of at least one of the first switch or the second switch based on the temporal behavior.

15 . The method of claim 14 , further comprising opening the first switch followed by opening the second switch prior to evaluating the temporal behavior.

16 . The method of claim 14 , further comprising charging the node to a first voltage prior to evaluating the temporal behavior, wherein the evaluating comprises evaluating a change of the voltage at the node to a second voltage.

17 . The method of claim 14 , further comprising:
placing the first and second switches in an open condition; closing the first switch; and pre-charging the node to a positive voltage, wherein evaluating the temporal behavior comprises evaluating if the voltage at the node drops sufficiently to a second voltage after closing the first switch.

18 . The method of claim 14 , further comprising providing a load between the first switch and the second switch.

19 . The method of claim 18 , further comprising:
coupling the load to a voltage supply by closing the first and second switches; and decoupling the load from the voltage supply by opening the first and second switches.

20 . The method of claim 14 , wherein evaluating the temporal behavior comprises controlling a timer.

Assignees

• Infineon Technologies Austria Ag

Inventors

• Mauder Anton
• Krupka Kay
• Barrenscheen Jens

Classifications

• G01R31/3277 Primary

  of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches · CPC title

• G01R31/2621

  for testing field effect transistors, i.e. FET's · CPC title

• H03K17/18 Primary

  Modifications for indicating state of switch · CPC title

• G01R31/3275 Primary

  Fault detection or status indication · CPC title

• G01R31/3272

  Apparatus, systems or circuits therefor (G01R31/3275 takes precedence) · CPC title