# US 11,908,529 B2 · Data storage device having over-voltage detection and protection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,908,529 B2 - Document ID: US11908529B2 - Status: Granted - Kind: B2 - Application number: 17/579,246 - Filed: 2022-01-19 - Published: 2023-07-20 - Granted: 2024-02-20 - Earliest claimed: 2022-01-19 - Assignees: Western Digital Technologies, Inc. - Applicants: Western Digital Technologies, Inc. - Inventors: Daniel J. Linnen; Kirubakaran Periyannan; Khanfer A. Kukkady - Web page: https://patentgrep.com/patent/US11908529B2 ## CPC - G11C 16/30: Power supply circuits - G11C 5/143: {Detection of memory cassette insertion or removal; Continuity checks of supply or ground lines; Detection of supply variations, interruptions or levels (G11C5/148 takes precedence); Switching between alternative supplies (G11C5/141 takes precedence)} - G11C 5/147: {Voltage reference generators, voltage or current regulators; Internally lowered supply levels; Compensation for voltage drops (G11C5/141 takes precedence)} - G11C 16/22: Safety or protection circuits preventing unauthorised or accidental access to memory cells - G11C 29/50: Marginal testing, e.g. race, voltage or current testing - H02H 3/087: for DC applications - H02H 3/202: {for DC systems} - H02H 9/041: {using a short-circuiting device} - G11C 17/16: using electrically-fusible links - G11C 2029/0409: {Online test} - G11C 2029/5004: {Voltage} - G11C: STATIC STORES (semiconductor memory devices H10B) - 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 A data storage device includes a power supply circuit configured to supply power to the data storage device. The power supply circuit includes a voltage clamp configured to operate in a conduction state in response to an over-voltage condition of the power supply circuit. The power supply circuit also includes a fuse in series with the voltage clamp. The fuse is configured to open in response to a current flow through the fuse and the voltage clamp exceeding a threshold value. The power supply circuit also includes a switching device that is configured to latch in a forward conduction mode in response to the voltage clamp operating in the conduction state. The switching device couples power from a positive voltage bus to the voltage clamp when the switching device is in the forward conduction mode. ## Claims ### Claim 1 A data storage device, comprising: a power supply circuit configured to supply power to the data storage device, the power supply circuit including: a voltage clamp configured to operate in a conduction state in response to an over-voltage condition of the power supply circuit; a fuse in series with the voltage clamp and the positive voltage bus, wherein the fuse is configured to open in response to a current flowing through the fuse and the voltage clamp exceeding a threshold value; and a switching device configured to latch in a forward conduction mode in response to the voltage clamp operating in the conduction state, wherein the switching device couples a positive voltage bus to the voltage clamp when operating in the forward conduction mode. ### Claim 2 (depends on 1) The data storage device of claim 1, wherein the switching device is a thyristor. ### Claim 3 (depends on 1) The data storage device of claim 1, wherein the voltage clamp is a Zener diode. ### Claim 4 (depends on 1) The data storage device of claim 1, further comprising an over-voltage detection circuit configured to generate an indication that an over-voltage condition has occurred. ### Claim 5 (depends on 4) The data storage device of claim 4, wherein the over-voltage detection circuit is a current-based over-voltage detection circuit configured to determine that the over-voltage condition has occurred based on detecting a switching device current flowing through the switching device. ### Claim 6 (depends on 4) The data storage device of claim 4, wherein the over-voltage detection circuit is a voltage-based over-voltage detection circuit configured to determine that the over-voltage condition has occurred based on a change in a voltage at an output of the switching device. ### Claim 7 (depends on 4) The data storage device of claim 4, further comprising a controller configured to: receive the indication from the over-voltage detection circuit that the over-voltage condition has occurred; and store a fault indicating that the over-voltage condition has occurred in a memory. ### Claim 8 (depends on 7) The data storage device of claim 7, wherein the controller is further configured to transmit the fault to an external device. ### Claim 9 A method performed by a data storage device having a controller coupled to a non-volatile memory device, the method comprising: detecting an occurrence of an over-voltage condition, wherein the over-voltage condition is detected by an over-voltage detection circuit; operating a voltage clamp of the data storage device in a conduction state in response to the occurrence of the over-voltage condition; latching a switching device of the data storage device in a forward conduction mode in response to the voltage clamp operating in the conduction state, wherein the switching device couples a positive voltage bus of a power supply circuit of the data storage device to the voltage clamp when operating in the forward conduction mode; receiving an indication of the detected occurrence of the over-voltage condition at the controller; storing the occurrence of the over-voltage condition in a memory; and transmitting the occurrence of the over-voltage condition to an external device. ### Claim 10 (depends on 9) The method of claim 9, further comprising disconnecting the data storage device from a power source in response to receiving the indication of the detected occurrence of the over-voltage condition. ### Claim 11 (depends on 9) The method of claim 9, wherein the over-voltage detection circuit is a current-based over-voltage detection circuit. ### Claim 12 (depends on 9) The method of claim 9, wherein the over-voltage detection circuit is a voltage-based over-voltage detection circuit. ### Claim 13 (depends on 9) The method of claim 9, wherein the over-voltage detection circuit includes an opto-coupler. ### Claim 14 A data storage device, comprising: a power supply circuit, including: a voltage clamp configured to operate in a conduction state in response to an over-voltage condition of the power supply circuit; a fuse in series with the voltage clamp and the positive voltage bus, wherein the fuse is configured to open in response to a current flowing through the fuse and the voltage clamp exceeding a threshold value; a switching device configured to latch in a forward conduction mode in response to the voltage clamp operating in the conduction state, wherein the switching device couples a positive voltage bus to the voltage clamp when operating in the forward conduction mode; and an over-voltage detection circuit configured to detect an occurrence of an over-voltage event. ### Claim 15 (depends on 14) The data storage device of claim 14, wherein the over-voltage detection circuit is a current-based over-voltage detection circuit configured to determine that an over-voltage condition has occurred based on the current flowing through the switching device. ### Claim 16 (depends on 14) The data storage device of claim 14, wherein the over-voltage detection circuit is a voltage-based over-voltage detection circuit configured to determine that an over-voltage condition has occurred based on a change in a voltage at an output of the switching device. ### Claim 17 (depends on 14) The data storage device of claim 14, further comprising a controller configured to: receive an indication from the over-voltage detection circuit that an over-voltage condition has occurred; and store the occurrence of the over-voltage condition in a memory. ### Claim 18 (depends on 17) The data storage device of claim 17, wherein the controller is further configured to transmit the occurrence of the over-voltage condition to an external device. ### Claim 19 (depends on 14) The data storage device of claim 14, wherein the switching device is a thyristor. ### Claim 20 (depends on 14) The data storage device of claim 14, wherein the voltage clamp is a Zener diode.