# US 12,003,089 B2 · Short to ground protection and automatic recovery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,089 B2 - Document ID: US12003089B2 - Status: Granted - Kind: B2 - Application number: 17/517,782 - Filed: 2021-11-03 - Published: 2022-05-05 - Granted: 2024-06-04 - Earliest claimed: 2020-11-05 - Assignees: Microchip Technology Incorporated - Applicants: Microchip Technology Incorporated - Inventors: Christopher Twigg; Zbigniew Lata; Fernando Gonzalez - Web page: https://patentgrep.com/patent/US12003089B2 ## CPC - H02H 3/08: responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) - H02H 3/087: for DC applications - H02H 1/0007: {concerning the detecting means (in general G01R or other subclasses of G01; reed switches H01H71/2445)} - H02H 3/06: with automatic reconnection - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) ## Abstract An apparatus includes a single sense pin connected to a line of a device connected to the apparatus, a gate pin configured to produce a gate signal to enable or disable a switch connected between the line of the device connected to the apparatus and a system ground, and control logic. The control logic is configured to at the single sense pin, determine a short between the device and the system ground, and, based upon the determination of the short, disable the switch. ## Claims ### Claim 1 An apparatus, comprising: a single sense pin connected to a line of a device connected to the apparatus; a gate pin to produce a gate signal to enable or disable a switch connected between the line of the device connected to the apparatus and a system ground; and a control logic to: enable a current source applied to the single sense pin to apply a first current to be received at the sense pin, the first current to cause a voltage drop across an offset resistor external to the apparatus on the line of the device connected to the apparatus, the switch, or a combination of the offset resistor and the switch, the voltage drop to indicate a short circuit when a magnitude of the voltage drop is above a threshold; at the single sense pin, determine the short circuit between the device and the system ground; and based upon the determination of the short, disable the switch. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the control logic is to enable a current sink to apply a second current to the single sense pin to measure voltage from the line. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the control logic is to disable the current source based upon the determination of the short circuit. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the control logic is to determine the short circuit between the device and the system ground at the single sense pin through a determination that voltage at the single sense pin is above a first voltage threshold. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the control logic is to determine that the short circuit has ended through a determination that voltage at the single sense pin has subsequently fallen below a second voltage threshold. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the first voltage threshold is higher than the second voltage threshold. ### Claim 7 (depends on 4) The apparatus of claim 4, wherein the control logic is to, based on a determination that voltage at the single sense pin previously exceeded the first voltage threshold, that voltage at the single sense pin is below the first voltage threshold, and that voltage at the single sense pin is above a second voltage threshold, continue to disable the switch. ### Claim 8 A method, comprising: at a gate pin, producing a gate signal to enable or disable a switch connected between a line of a device and a system ground; enabling a current source applied to a single sense pin connected to a line of the device to apply a first current to be received at the single sense pin, the first current to cause a voltage drop across an offset resistor external to the apparatus on the line of the device, the switch, or a combination of the offset resistor and the switch, the voltage drop to indicate a short circuit when a magnitude of the voltage drop is above a threshold; at the single sense pin, determining the short circuit between the device and the system ground; based on a determination of the short circuit between the device and the system ground, disabling the switch. ### Claim 9 (depends on 8) The method of claim 8, comprising enabling a current sink to measure voltage from the line. ### Claim 10 (depends on 8) The method of claim 8, comprising disabling the current source based upon the determination of the short circuit. ### Claim 11 (depends on 8) The method of claim 8, wherein the method comprises determining the short circuit between the device and the system ground at the single sense pin through a determination that voltage at the single sense pin is above a first voltage threshold. ### Claim 12 (depends on 11) The method of claim 11, comprising determining that the short circuit has ended through a determination that voltage at the single sense pin has subsequently fallen below a second voltage threshold. ### Claim 13 (depends on 12) The method of claim 12, wherein the first voltage threshold is higher than the second voltage threshold. ### Claim 14 (depends on 11) The method of claim 11, comprising, based on a determination that voltage at the single sense pin previously exceeded the first voltage threshold, that voltage at the single sense pin is below the first voltage threshold, and that voltage at the single sense pin is above a second voltage threshold, continue to disable the switch. ### Claim 15 A system, comprising: a single sense pin connected to a line, the line to connect the system and a connector to an external device; a switch coupled between the line and system ground; a gate pin to produce a gate signal to enable or disable the switch connected between the line of the external device connected to the apparatus and a system ground; and a control logic to: enable a current source applied to the single sense pin to apply a first current to be received at the single sense pin, the first current to cause a voltage drop across an offset resistor external to the apparatus on the line of the external device connected to the apparatus, the switch, or a combination of the offset resistor and the switch, the voltage drop to indicate a short circuit when a magnitude of the voltage drop is above a threshold; at the single sense pin, determine the short circuit between the external device and the system ground; and based upon the determination of the short, disable the switch. ### Claim 16 (depends on 15) The system of claim 15, wherein the control logic is to enable a current sink to measure voltage from the line. ### Claim 17 (depends on 15) The system of claim 15, wherein the control logic is to disable the current source based upon the determination of the short circuit.