Over-voltage detection and port protection
Redundancy in over-voltage fault protection may be provided by controlling switches already present in a power path of a port for an information handling system. An external device coupled to a port may be decoupled from the system when an over-voltage condition is detected at another port of the information handling system. To decouple an external device upon detection of an over-voltage condition, a switch coupled to the port and the external device is turned off. A battery may also be decoupled from a port upon detection of an over-voltage condition at another port.
1. An apparatus, comprising:
a first port configured to provide a first power path for coupling a first external device to an information handling system;
a second port configured to provide a second power path for coupling a second external device to the information handling system; and
a first over-voltage detector coupled to the second port,
wherein the first over-voltage detector is configured to monitor the second power path for an over-voltage condition and, when the over-voltage condition is detected, turn off a first switch of the first port to decouple the first external device from the information handling system.
2. The apparatus of claim 1 , wherein the first over-voltage detector is configured to block reverse current from the first external device to the second external device by turning off the switch, and wherein the first over-voltage detector is configured to monitor the second power path for a failure of a second switch of the second port by detecting an over-voltage condition on the second power path.
3. The apparatus of claim 2 , wherein the first switch comprises a soft-start power metal-oxide-semiconductor field-effect transistor (MOSFET), and wherein the second switch comprises a DC-blocking MOSFET.
4. The apparatus of claim 2 , further comprising a port controller coupled to the first port, wherein the port controller is configured to turn off the second switch of the second port when the first port is coupled to the first external device in a high-power mode.
5. The apparatus of claim 1 , further comprising a second over-voltage detector coupled to the first port, wherein the second over-voltage detector is configured to monitor the first power path for an over-voltage condition and, when the over-voltage condition of the first power path is detected, turn off a second switch of the second port to decouple the second external device.
6. The apparatus of claim 5 , further comprising a port controller coupled to the first port, wherein the port controller is configured to detect the external device coupled to the first port in a high-power mode and to deactivate the second over-voltage detector when the external device is coupled to the first port in the high-power mode.
7. The apparatus of claim 1 , wherein the first port comprises a USB type-C port and the second port comprises a USB type-C port.
8. The apparatus of claim 1 , wherein the first port comprises a barrel power connector.
9. The apparatus of claim 1 , further comprising a battery and a second switch coupled between the battery and the first and second ports, wherein the first over-voltage detector is configured to turn off the second switch when the over-voltage condition is detected, to prevent reverse current from flowing from the battery to the first port or the second port.
10. An information handling system, comprising:
a battery;
a charger coupled to the battery;
a first port coupled to the charger and to the second port;
a second port coupled to the charger and to the first port;
a first over-voltage detector coupled to the second port; and
a first switch coupled to the first port configured to block reverse current to the second port,
wherein the first over-voltage detector is configured to turn off the first switch when the first over-voltage detector detects an over-voltage condition at the second port.
11. The information handling system of claim 10 , wherein turning off the first switch blocks reverse current from a first device coupled to the first port to a second device coupled to the second port.
12. The information handling system of claim 10 , further comprising:
a second over-voltage detector coupled to the first port; and
a second switch coupled to the second port configured to block reverse current to the first port,
wherein the second over-voltage detector is configured to turn off the second switch when the second over-voltage detector detects an over-voltage condition at the first port.
13. The information handling system of claim 10 , further comprising a second switch coupled to the second port, wherein the first over-voltage detector is configured to turn off the first switch to decouple a first external device coupled to the first port, when the first over-voltage detector detects an over-voltage condition at the second port due to a failure of the second switch.
14. The information handling system of claim 13 , wherein the first switch comprises a soft-start power metal-oxide-semiconductor field-effect transistor (MOSFET), and wherein the second switch comprises a DC blocking MOSFET.
15. The information handling system of claim 13 , further comprising a port controller coupled to the first port, wherein the port controller is configured to turn off the second switch of the second port when the first port is coupled to an external device in a high-power mode, to block reverse current to the second port.
16. The information handling system of claim 10 , wherein the first port comprises a USB type-C port and the second port comprises a USB type-C port.
17. The information handling system of claim 10 , further comprising a second switch coupled between the battery and the first and second ports, wherein the first over voltage detector is configured to turn off the second switch when the over-voltage condition is detected, to prevent reverse current from flowing from the battery to the first or second ports.
18. A method, comprising:
detecting an over-voltage condition at a second port of an information handling system; and
when the over-voltage condition is detected, turning off a first switch coupled between a first port of the information handling system and the second port to block reverse current from the first port to the second port.
19. The method of claim 18 , further comprising:
detecting an external device coupled to the first port in a high-power mode; and
when the external device is detected, turning off a second switch coupled between the first port and the second port of the information handling system to block reverse current to the second port while allowing power to be delivered to the information handling system from the device coupled to the first port.
20. The method of claim 18 , wherein turning off the first switch comprises decoupling the external device coupled to the first port of the information handling system from the information handling system.