THERMAL PROTECTION CIRCUITS FOR ELECTRONIC DEVICE CABLES

• US 20110104940A1
• Filed: 11/03/2009
• Published: 05/05/2011
• Est. Priority Date: 11/03/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Hollabaugh, James M., Rabu, Stanley
• Granted Patent: US 8,498,087 B2
• Time in Patent Office: Days
• US Class Current: 439/502
• CPC Class Codes: H01R 13/7137 with thermal interrupter H01R13/7132 takes precedence
• CPC Class Codes: H01R 31/065 with built-in electric apparatus

Abstract

Connectors for cables such as a 30-pin connector are provided. The connectors may have thermal protection circuits and may carry a power supply voltage and a ground voltage. The thermal protection circuits may disable the power supply voltage when the temperature of the connector exceeds a threshold value. The thermal protection circuits may disable the power supply voltage when liquid is detected in the connector. The thermal protection circuits may disable the power supply voltage permanently or temporarily. In one example, when a cable is reset, the thermal protection circuits may use a record of previous fault events and measurements from thermal and liquid sensors to determine whether to enable or disable the power supply voltage.

Claims

1. A cable, comprising:

at least a pair of conductive lines;

first and second connectors coupled to respective ends of the lines; and

thermal protection circuitry that includes;

a cutoff switch interposed in at least one of the lines; and

a fuse, wherein the thermal protection circuitry is configured to close the switch when the fuse is intact.

2. The cable defined in claim 1 further comprising at least one sensor that takes readings.

3. The cable defined in claim 2 wherein the sensor is located in the first connector and wherein the thermal protection circuitry is configured to blow the fuse based on the readings taken by the sensor.

4. The cable defined in claim 1 further comprising a moisture sensor in the first connector, wherein the thermal protection circuitry is configured to blow the fuse when the moisture sensor detects moisture in the first connector.

5. The cable defined in claim 1 further comprising a moisture sensor in the first connector that includes a pair of conductors separated by a gap, wherein the thermal protection circuitry is configured to blow the fuse when moisture in the first connector electrically couples the pair of conductors together across the gap.

6. The cable defined in claim 1 further comprising a temperature sensor in the first connector, wherein the thermal protection circuitry is configured to blow the fuse when the temperature sensor detects that the temperature of the first connector has exceeded a threshold temperature.

7. The cable defined in claim 6 wherein the temperature sensor comprises a thermistor.

8. The cable defined in claim 7 wherein the thermistor comprises a thermistor having a negative temperature coefficient.

9. The cable defined in claim 1 further comprising a moisture sensor in the first connector and a temperature sensor in the first connector, wherein the thermal protection circuitry is configured to blow the fuse when the moisture sensor detects moisture in the first connector and wherein the thermal protection circuitry is configured to blow the fuse when the temperature sensor detects that the temperature of the first connector has exceeded a threshold temperature.

10. A cable, comprising:

at least a pair of conductive lines;

first and second connectors coupled to respective ends of the lines;

a cutoff switch interposed in at least one of the lines; and

moisture sensor circuitry coupled to the cutoff switch.

11. The cable defined in claim 10 wherein the moisture sensor circuitry comprises a pair of conductors separated by a gap.

12. The cable defined in claim 11 further comprising a printed circuit board in the first connector, wherein the printed circuit board has a perimeter and wherein the pair of conductors are formed on at least part of the perimeter of the printed circuit board.

13. The cable defined in claim 11 further comprising a printed circuit board in the first connector, wherein the printed circuit board has a perimeter and wherein the pair of conductors are arranged in a ring that extends around a majority of the of the perimeter of the printed circuit board.

14. The cable defined in claim 11 further comprising a fuse, wherein the fuse, the cutoff switch, and the moisture sensor circuitry are part of thermal protection circuitry, wherein the thermal protection circuitry is configured to close the switch when the fuse is intact, and wherein the thermal protection circuitry is configured to blow the fuse when moisture electrically couples the pair of conductors together across the gap.

15. The cable defined in claim 14 further comprising:

a temperature sensor in the first connector, wherein the thermal protection circuitry is configured to blow the fuse when the temperature sensor detects that the temperature of the first connector has exceeded a threshold temperature.

16. The cable defined in claim 15 wherein the temperature sensor comprises a thermistor.

17. A method, comprising:

gathering real time sensor data with sensor circuitry in a cable that has at least a pair of lines with connectors at either end;

retrieving information from storage indicative of previously stored sensor data; and

preventing power flow through at least one of the lines based at least partly on the retrieved information and at least partly on the real time sensor data.

18. The method defined in claim 17 wherein gathering the real time sensor data with the sensor circuitry comprises gathering sensor data with a moisture sensor.

19. The method defined in claim 17 wherein gathering the real time sensor data with the sensor circuitry comprises gathering real time temperature data with a thermistor and wherein the storage comprises a fuse, the method further comprising:

blowing the fuse in response to temperature data from the thermistor that indicates that the temperature of one of the connectors has exceeded a threshold temperature.

20. The method defined in claim 17 wherein gathering the real time sensor data with the sensor circuitry comprises gathering real time moisture data with a moisture sensor and gathering real time temperature data with a thermistor, wherein the storage comprises at least first and second fuses, the method further comprising:

blowing the first fuse in response to real time temperature data from the thermistor that indicates that the temperature of one of the connectors has exceeded a threshold temperature; and

blowing the second fuse in response to real time moisture data from the moisture sensor that indicates that moisture has infiltrated one of the connectors.