Solid state resettable fuses

Patent metadata

Field	Value
Publication number	US-9998117-B2
Application number	US-201514965385-A
Country	US
Kind code	B2
Filing date	Dec 10, 2015
Priority date	Dec 10, 2015
Publication date	Jun 12, 2018
Grant date	Jun 12, 2018

Abstract

A resettable solid state fuse that automatically restores an interrupted circuit after an overcurrent event is cleared. The resettable solid state fuse can include one or more switching devices, such as, for example, a normally-on power semiconductor, and one or more positive temperature coefficient (PTC) resistive elements. The switching device is structured to extend the voltage rating of the resettable fuse, allowing the solid state resettable fuse to attain both a relatively elevated voltage rating and a relatively elevated electrical current rating while using a PTC resistive element. According to certain embodiments, the solid state resettable fuse can be tripped by a cascaded PTC resistive element, thereby providing a passive electronic device that can operate in the absence of electronic sensing, detection, and tripping, as well as without reliance on an auxiliary power supply.

First claim

The invention claimed is:

1. A solid state resettable fuse comprising:
a positive temperature coefficient resistive component being automatically resettable from a high electrical resistance state to a low electrical resistance state, the positive temperature coefficient resistive component having a resistance to a flow of an electrical current through the positive temperature coefficient resistive component, the resistance being higher for the high electrical resistance state than for the low electrical resistance state; and
a normally-on switch device having a control terminal electrically coupled to the positive temperature coefficient resistive component, the control terminal configured to receive a control signal at least when the positive temperature coefficient resistive component is in the high electrical resistance state, the control terminal configured to adjust the normally-on switch device from an on state to a tripped state in response to the received control signal, and
wherein the solid state resettable fuse outputs a leakage current when the normally-on switch device is in the tripped state.

2. The solid state resettable fuse of claim 1 , wherein the control signal is a gate-source voltage.

3. The solid state resettable fuse of claim 2 , wherein the gate-source voltage is a negative voltage.

4. The solid state resettable fuse of claim 2 , wherein the positive temperature coefficient resistive component is in the low electrical resistance state when a temperature of the positive temperature coefficient resistive component is below a threshold temperature, and wherein the positive temperature coefficient resistive component is in the high electrical resistance state when the temperature of the positive temperature coefficient resistive component exceeds the threshold temperature.

5. The solid state resettable fuse of claim 4 , wherein the normally-on switch device is a normally-on wide bandgap semiconductor, and wherein the control terminal is a gate.

6. The solid state resettable fuse of claim 5 , wherein the solid state resettable fuse is a passive electronic device.

7. The solid state resettable fuse of claim 4 , wherein the positive temperature coefficient resistive component is a polymer positive temperature coefficient resettable fuse.

8. The solid state resettable fuse of claim 4 , wherein the positive temperature coefficient resistive component is one of a bi-metal based thermal breaker and a memory shape alloy based thermal breaker.

9. The solid state resettable fuse of claim 4 , wherein the positive temperature coefficient resistive component comprises a polymer positive temperature coefficient resettable fuse that is connected in parallel to a bi-metal based thermal breaker or a memory shape alloy based thermal resistor.

10. The solid state resettable fuse of claim 1 , wherein the normally-on switch device comprises a plurality of normally-on power semiconductors connected to the positive temperature coefficient resistive component in a super cascade arrangement.

11. The solid state resettable fuse of claim 1 , further including a switch in electrical communication with the normally-on switch device, the switch structure to provide galvanic isolation so as to prevent current flow in response to an overcurrent event.

12. A solid state resettable fuse comprising:
a positive temperature coefficient resistive component having a low electrical resistance state and a high electrical resistance state, the positive temperature coefficient resistive component configured to reset from the high electrical resistance state to the low electrical resistance state in response to a temperature of the positive temperature coefficient resistive component being below a threshold temperature; and
a first normally-on switch device in a cascade arrangement with the positive temperature coefficient resistive component, the first normally-on switch device adjustable from at least a first on state to a first tripped state in response to at least the positive temperature coefficient resistive component being transitioned from the low electrical resistance state to the high electrical resistance state, and wherein the solid state resettable fuse outputs a leakage electrical current at least when the first normally-on switch device is in the first tripped state.

13. The solid state resettable fuse of claim 12 , wherein the positive temperature coefficient resistive component transitions from the low electrical resistance state to the high electrical resistance state at least when the temperature exceeds the threshold temperature.

14. The solid state resettable fuse of claim 13 , wherein the normally-on switch device is a normally-on wide bandgap semiconductor.

15. The solid state resettable fuse comprising of claim 14 , wherein the normally-on switch device includes a control terminal that is adjustable in response to a voltage drop across the positive temperature coefficient resistive component at least when the positive temperature coefficient resistive component transitions from the low electrical resistance state to the high electrical resistance state.

16. The solid state resettable fuse of claim 15 , wherein the positive temperature coefficient resistive component is a polymer positive temperature coefficient resettable fuse.

17. The solid state resettable fuse of claim 15 , wherein the positive temperature coefficient resistive component is one of a bi-metal based thermal breaker and a memory shape alloy based thermal breaker.

18. The solid state resettable fuse of claim 15 , wherein the positive temperature coefficient resistive component comprises a polymer positive temperature coefficient resettable fuse that is connected in parallel to a bi-metal based thermal breaker or a memory shape alloy based thermal resistor.

19. The solid state resettable fuse of claim 12 , further including a second normally-on switch device in a cascade arrangement with the positive temperature coefficient resistive component, the second normally-on switch device adjustably operable in at least a second on state and a second tripped state in response to at least the positive temperature coefficient resistive component being transitioned from the low electrical resistance state to the high electrical resistance state.

20. The solid state resettable fuse of claim 19 , wherein the first normally-on switch device is configured to be in the first tripped state when the positive temperature coefficient resettable is in the high electrical resistance state and the solid state resettable fuse is receiving a current having a first polarity, the second normally-on switch device being in a on state when the first normally-on switch device is in the first tripped state, and
wherein the second normally-on switch device is configured to be in the second tripped state when the positive temperature coefficient resettable is in the high electrical resistance state and the solid state resettable fuse is receiving a current having a second polarity that is opposite of the first polarity, the first normally-on switch device being in a on state when the second normally-on switch device is in the second tripped state.

21. The solid state resettable fuse of claim 20 , wherein the first normally-on switch device is electrically coupled to a first gate resistor and a first Zener diode, the first gate resistor and the first Zener diode being arranged to prevent a high gate current of the first normally-on switch device, and further wherein the second

Assignees

• Abb Schweiz Ag

Inventors

• Du Yu
• Kim Hongrae
• Jiang Taosha

Classifications

• H03K17/687

  the devices being field-effect transistors · CPC title

• H03K17/94 Primary

  characterised by the way in which the control signals are generated · CPC title

• H01C7/06

  including means to minimise changes in resistance with changes in temperature · CPC title

• H01H2085/0283

  Structural association with a semiconductor device · CPC title

• H01C7/02

  having positive temperature coefficient · CPC title