# US 9,003,559 B2 · Continuity check monitoring for microchip exploitation detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,003,559 B2 - Document ID: US9003559B2 - Status: Granted - Kind: B2 - Application number: 12/181,357 - Filed: 2008-07-29 - Published: 2010-02-04 - Granted: 2015-04-07 - Earliest claimed: 2008-07-29 - Assignees: International Business Machines Corporation - Applicants: Gerald K. Bartley; Darryl J. Becker; Paul E. Dahlen; Philip R. Germann; Andrew B. Maki; Mark O. Maxson; Carl-Otto Nilsen - Inventors: Gerald K. Bartley; Darryl J. Becker; Paul E. Dahlen; Philip R. Germann; Andrew B. Maki; Mark O. Maxson; Carl-Otto Nilsen - Web page: https://patentgrep.com/patent/US9003559B2 ## CPC - G06F 21/87: by means of encapsulation, e.g. for integrated circuits - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Apparatus, method and program product detect an attempt to tamper with a microchip by determining that an electrical path comprising one or more connections and a metal plate attached to the backside of a microchip has become disconnected or otherwise altered. A tampering attempt may also be detected in response to the presence of an electrical path that should not be present, as may result from the microchip being incorrectly reconstituted. Actual and/or deceptive paths may be automatically selected and monitored to further confound a reverse engineering attempt. ## Claims ### Claim 1 An apparatus comprising: an electrical path configured to electrically connect a plurality of first connections, wherein the plurality of first connections are first connecting points in first circuitry of a microchip, and wherein the electrical path comprises a conductive element; a false electrical path configured to appear to connect a plurality of second connections but not electrically connecting the plurality of second connections, wherein the plurality of second connections are second connecting points in the first circuitry of the microchip; and second circuitry configured to detect a disconnection of the electrical path, a connection of the false electrical path, or a combination thereof resulting from a reverse engineering process targeting the first circuitry, and to initiate an action to obstruct the reverse engineering process, wherein the second circuitry is in electrical communication with the electrical path and with the false electrical path, and wherein the second circuitry is embedded with the first circuitry. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the conductive element comprises a metallic plate. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the conductive element is positioned on a backside of the microchip. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the plurality of first connections are selected automatically, randomly, or a combination thereof for inclusion within the electrical path. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the plurality of second connections are selected automatically, randomly, or a combination thereof for inclusion within the false electrical path. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the plurality of first connections and the plurality of second connections include through-silicon vias. ### Claim 7 (depends on 1) The apparatus of claim 1, further comprising a signal transmitter configured to transmit a signal to the electrical path. ### Claim 8 (depends on 1) The apparatus of claim 1, further comprising a signal receiver configured to receive a signal from the electrical path. ### Claim 9 (depends on 1) The apparatus of claim 1, further comprising a bus configured to facilitate automatic selection, random selection, or a combination thereof of first connections for inclusion within the electrical path. ### Claim 10 (depends on 1) The apparatus of claim 1, further comprising a bus configured to facilitate automatic selection, random selection, or a combination thereof of second connections for inclusion within the false electrical path. ### Claim 11 (depends on 1) The apparatus of claim 1, further comprising program code executed by the second circuitry and configured to initiate the action for obstructing the reverse engineering process, and a computer readable storage device storing the program code. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the action includes a shutdown operation, a spoofing operation, a self-destruct operation, or any combination thereof. ### Claim 13 An apparatus comprising: a false electrical path configured to appear to connect a plurality of connections but not electrically connecting the plurality of connections, wherein the plurality of connections are connecting points in first circuitry of a microchip; and second circuitry configured to detect a connection of the false electrical path resulting from a reverse engineering process targeting the first circuitry and to initiate an action to obstruct the reverse engineering process, wherein the second circuitry is in electrical communication with the false electrical path, and wherein the second circuitry is embedded with the first circuitry. ### Claim 14 A method of protecting security sensitive circuitry of a microchip from undesired analysis, the method comprising: initializing the microchip; selecting an electrical path from among a plurality of electrical paths, wherein the electrical path is configured to electrically connect a plurality of first connections, and wherein the plurality of first connections are connecting points in first circuitry of the microchip; selecting a false electrical path from among a plurality of false electrical paths, wherein the false electrical path is configured to appear to connect a plurality of second connections but to not electrically connect the plurality of second connections, and wherein the plurality of second connections are second connecting points in the first circuitry of the microchip; detecting, by second circuitry, a disconnection of the electrical path, a connection of the false electrical path, or a combination thereof resulting from a reverse engineering process targeting the first circuitry, wherein the second circuitry is in electrical communication with the electrical path and with the false electrical path; and initiating an action to obstruct the reverse engineering process, wherein the second circuitry is embedded with the first circuitry. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein the second circuitry comprises: a plurality of comparators; a NAND gate; and a defensive circuit, wherein the plurality of comparators are configured to compare input signals from the plurality of first connections of the electrical path and the plurality of second connections of the false electrical path with reference signals and to output results to the NAND gate, wherein the NAND gate is configured to output a signal to the defensive circuit in response to the results from the plurality of comparators, and wherein the defensive circuit is configured to initiate the action to obstruct the reverse engineering process when the signal from the NAND gate indicates the disconnection of the electrical path, the connection of the false electrical path, or a combination thereof. ### Claim 16 (depends on 13) The apparatus of claim 13, wherein the second circuitry comprises: a plurality of comparators; a NAND gate; and a defensive circuit, wherein the plurality of comparators are configured to compare input signals from the plurality of connections of the false electrical path with reference signals and to output results to the NAND gate, wherein the NAND gate is configured to output a signal to the defensive circuit in response to the results from the plurality of comparators, and wherein the defensive circuit is configured to initiate the action to obstruct the reverse engineering process when the signal from the NAND gate indicates the connection of the false electrical path. ### Claim 17 (depends on 14) The method of claim 14, wherein the second circuitry comprises: a plurality of comparators; a NAND gate; and a defensive circuit, wherein the plurality of comparators are configured to compare input signals from the plurality of connections of the electrical path and the plurality of second connections of the false electrical path with reference signals and to output results to the NAND gate, wherein the NAND gate is configured to output a signal to the defensive circuit in response to the results from the plurality of comparators, and wherein the defensive circuit is configured to initiate the action to obstruct the reverse engineering process when the signal from the NAND gate indicates the disconnection of the electrical path, the connection of the false electrical path, or a combination thereof. ### Claim 18 (depends on 13) The apparatus of claim 13, wherein the plurality of connections are selected automatically, randomly, or a combination thereof for inclusion within the false electrical path, and wherein the plurality of connections include through-silicon vias.