# US 2013/0159797 A1 · Apparatus and methods for indicating the health of removable storage devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0159797 A1 - Document ID: US20130159797A1 - Status: Published application - Kind: A1 - Application number: 13/331,491 - Filed: 2011-12-20 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: SanDisk Technologies LLC - Inventors: Yong Peng; Ka Ian Yung; Xiangyang Miao; Arjun Hary - Web page: https://patentgrep.com/patent/US20130159797A1 ## CPC - G11C 16/349: {Arrangements for evaluating degradation, retention or wearout, e.g. by counting erase cycles} - G11C 2029/0409: {Online test} - G11C: STATIC STORES (semiconductor memory devices H10B) ## Abstract Disclosed are apparatus and techniques for indicating health of a memory system having a controller and nonvolatile memory array. In one embodiment, the invention pertains to a method for indicating health of a removable memory system that is removably coupled with a host device. After the memory system is coupled with a host device, a first health status is output via an external electrical or mechanical interface of the memory system. One or more health metrics of the memory system are monitored. After a first predefined limit is reached with respect to the one or more health metrics, a second health status is output via the external electrical or mechanical interface of the memory system. The first health status differs from the second health status. ## Claims ### Claim 1 A method for indicating health of a removable memory system that is removably coupled with a host device, the method comprising: after the memory system is coupled with a host device, outputting a first health status via an external electrical or mechanical interface of the memory system; monitoring one or more health metrics of the memory system; and after a first predefined limit is reached with respect to the one or more health metrics, outputting a second health status via the external electrical or mechanical interface of the memory system, wherein the first health status differs from the second health status. ### Claim 2 (depends on 1) The method of claim 1, wherein the first health status indicates that the host device is allowed to perform data operations, including programming operations, with respect to the memory system. ### Claim 3 (depends on 2) The method of claim 2, wherein the first predefined limit is a first programming or erase count limit and the second health status indicates that the memory system is close to its maximum programming or erase count limit for allowing programming operations from the host to the memory system to continue. ### Claim 4 (depends on 3) The method of claim 3, further comprising: after a second predefined limit is reached with respect to the one or more health metrics, converting the memory system to read only mode after the memory system is decoupled from the host device or the host device remains idle for more than a predefined time duration. ### Claim 5 (depends on 4) The method of claim 4, further comprising: after a third predefined limit is reached with respect to the one or more health metrics, outputting a third health status via the external electrical or mechanical interface of the memory system and converting the memory system to read only mode even if the memory system remains coupled with the host device, wherein the second predefined limit is a second programming or erase count limit that is higher than the first programming or erase count limit and the third predefined count limit is a third programming or erase count limit that is higher than the second programming or erase count limit, wherein the third health status differs from the first and second health status, and wherein the third health status indicates that the memory system has reached the end of its programming life. ### Claim 6 (depends on 5) The method of claim 5, wherein the memory system is converted to read only mode after the third predefined limit is reached, even if the host device remains idle for more than a predefined duration of time or the host device is active. ### Claim 7 (depends on 6) The method of claim 6, wherein the electrical or mechanical interface is a light device, and the first health status causes the light device to breath slowly, the second health status causes the light device to blink rapidly, and the third health status causes the light device to remain on. ### Claim 8 (depends on 5) The method of claim 5, further comprising: querying the host device as to whether the memory system is to be converted into read only mode; and if the host device indicates that the memory system is not to be converted into read only mode, stopping the memory system from being converted to read only mode or converting the memory system back to a programming mode. ### Claim 9 (depends on 8) The method of claim 8, further comprising: informing the host device that if the memory system is not to be converted to read only mode, data retention of a predefined maximum time duration cannot be guaranteed. ### Claim 10 (depends on 1) The method of claim 1, wherein the one or more health metrics comprise one or more of the following: a hot count metric, an error rate metric, or read disturb. ### Claim 11 A method for indicating health of a removable memory system, the method comprising: after the memory system is coupled with a host device, outputting from the memory system a first externally visible or audible health indicator that indicates that the memory system is programmable by the host device; tracking a hot count for performing an erase cycle on each memory cell block of the memory system to determine whether the hot count has reached one of a plurality of hot count thresholds; if the hot count reaches a first one of the hot count thresholds, outputting from the memory system a second externally visible or audible health indicator that indicates that the memory system is about to be converted to a read only mode; and if the hot count reaches a second one of the hot count thresholds, outputting from the memory system a third externally visible or audible health indicator that indicates that the memory system is being immediately converted to a read only mode. ### Claim 12 A memory system that is removably couplable with a host device, the memory system comprising: an external electrical or mechanical interface coupled with a controller; a nonvolatile memory array for storing data and coupled with the controller; and the controller operable to perform the following operations: after the memory system is coupled with a host device, outputting a first health status via the external electrical or mechanical interface of the memory system; monitoring one or more health metrics of the memory system; and after a first predefined limit is reached with respect to the one or more health metrics, outputting a second health status via the external electrical or mechanical interface of the memory system, wherein the first health status differs from the second health status. ### Claim 13 (depends on 11) The memory system of claim 11, wherein the first health status indicates that the host device is allowed to perform data operations, including programming operations, with respect to the memory system. ### Claim 14 (depends on 13) The memory system of claim 13, wherein the first predefined limit is a first programming or erase count limit and the second health status indicates that the memory system is close to its maximum programming or erase count limit for allowing programming operations from the host to the memory system to continue. ### Claim 15 (depends on 14) The memory system of claim 14, the controller further operable to perform the following operations: after a second predefined limit is reached with respect to the one or more health metrics, converting the memory system to read only mode after the memory system is decoupled from the host device or the host device remains idle for more than a predefined time duration. ### Claim 16 (depends on 15) The method of claim 15, the controller further operable to perform the following operations: after a third predefined limit is reached with respect to the one or more health metrics, outputting a third health status via the external electrical or mechanical interface of the memory system and converting the memory system to read only mode even if the memory system remains coupled with the host device, wherein the second predefined limit is a second programming or erase count limit that is higher than the first programming or erase count limit and the third predefined count limit is a third programming or erase count limit that is higher than the second programming or erase count limit, wherein the third health status differs from the first and second health status, and wherein the third health status indicates that the memory system has reached the end of its programming life. ### Claim 17 (depends on 16) The memory system of claim 16, wherein the memory system is converted to read only mode after the third predefined limit is reached, even if the host device remains idle for more than a predefined duration of time or the host device is active. ### Claim 18 (depends on 17) The memory system of claim 17, wherein the electrical or mechanical interface is a light device, and the first health status causes the light device to breath slowly, the second health status causes the light device to blink rapidly, and the third health status causes the light device to remain on. ### Claim 19 (depends on 16) The memory system of claim 16, the controller further operable to perform the following operations: querying the host device as to whether the memory system is to be converted into read only mode; and if the host device indicates that the memory system is not to be converted into read only mode, stopping the memory system from being converted to read only mode or converting the memory system back to a programming mode. ### Claim 20 (depends on 19) The memory system of claim 19, the controller further operable to perform the following operations: informing the host device that if the memory system is not to be converted to read only mode, data retention of a predefined maximum time duration cannot be guaranteed. ### Claim 21 (depends on 11) The memory system of claim 11, wherein the one or more health metrics comprise one or more of the following: a hot count metric, an error rate metric, or read disturb.