# US 2017/0288385 A1 · Short-circuit protection circuit for self-arc-extinguishing type semiconductor element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0288385 A1 - Document ID: US20170288385A1 - Status: Published application - Kind: A1 - Application number: 15/505,812 - Filed: 2014-09-11 - Published: 2017-10-05 - Earliest claimed: 2014-09-11 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Yoshitaka NAKA; Yasushi NAKAYAMA; Yoshiko TAMADA; Hiroyuki TAKAGI; Junichiro ISHIKAWA; Kazuhiro OTSU; Naohiko MITOMI - Web page: https://patentgrep.com/patent/US20170288385A1 ## CPC - H02H 3/08: responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) - H02M 7/5387: in a bridge configuration - H03K 17/0822: {in field-effect transistor switches} - H10D 12/411: {Insulated-gate bipolar transistors [IGBT]} - H10D 89/921: {characterised by the configuration of the interconnections connecting the protective arrangements, e.g. ESD buses} - 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) - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract A short-circuit protection circuit for a self-arc-extinguishing type semiconductor element includes a first protection circuit and a second protection circuit. The first protection circuit is configured to reduce a voltage between a control electrode and a first main electrode of the self-arc-extinguishing type semiconductor element when detecting overcurrent flowing between the first main electrode and a second main electrode. The second protection circuit is configured to: detect current flowing in an interconnection adapted to supply the drive voltage; determine, based on the detected current, whether the first protection circuit is in an operating state; and change the drive voltage to turn off the self-arc-extinguishing type semiconductor element when the first protection circuit is in the operating state. ## Claims ### Claim at position 1 1-9. (canceled) ### Claim 10 A short-circuit protection circuit for a self-arc-extinguishing type semiconductor element, the self-arc-extinguishing type semiconductor element including a first main electrode, a second main electrode, and a control electrode, and configured to be switched on to be conductive between the first main electrode and the second main electrode or switched off to be non-conductive between the first main electrode and the second main electrode, in response to a drive voltage supplied between the control electrode and the first main electrode, the short-circuit protection circuit comprising: a first protection circuit configured to reduce a voltage between the control electrode and the first main electrode when detecting overcurrent flowing between the first main electrode and the second main electrode; and a second protection circuit configured to: detect current flowing in an interconnection adapted to supply the drive voltage; and change, when the first protection circuit is in an operating state, the drive voltage to turn off the self-arc-extinguishing type semiconductor element. ### Claim 11 (depends on 10) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 10, wherein the second protection circuit includes an operation determination circuit configured to determine, based on the detected current, whether the first protection circuit is in an operating state. ### Claim 12 (depends on 11) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 11, wherein the drive voltage is supplied from a drive circuit connected through a control interconnection to the control electrode of the self-arc-extinguishing type semiconductor element, the second protection circuit further includes a gate resistance element disposed on the control interconnection, and the operation determination circuit is configured to determine whether the first protection circuit is in an operating state, based on a voltage generated at the gate resistance element. ### Claim 13 (depends on 12) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 12, wherein the operation determination, circuit includes: a delay circuit configured to output a voltage which is changed with a delay relative to a change of the voltage generated at the gate resistance element; and a determination unit configured to determine that the first protection circuit is in an operating state, when the voltage which is output from the delay circuit exceeds a threshold voltage. ### Claim 14 (depends on 13) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 13, wherein the operation determination circuit further includes a voltage limitation circuit provided between the gate resistance element and the delay circuit and configured to limit a magnitude of a voltage which is input from the gate resistance element to the delay circuit. ### Claim 15 (depends on 13) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 13, wherein the delay circuit is configured as an RC filter circuit including a resistance element and a capacitor, and the RC filter circuit is configured to have a smaller time constant when the capacitor is being discharged relative to a time constant when the capacitor is being charged. ### Claim 16 (depends on 13) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 13, wherein the operation determination circuit further includes a voltage reduction circuit provided between the delay circuit and the determination unit and configured to reduce a magnitude of a voltage which is input from the delay circuit to the determination unit. ### Claim 17 (depends on 12) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 12, wherein the drive circuit is configured to output the drive voltage for switching on the self-arc-extinguishing type semiconductor element and output the drive voltage for switching off the self-arc-extinguishing type semiconductor element, in response to an ON signal and an OFF signal, respectively, and the operation determination circuit includes: a determination unit configured to determine that the first protection circuit is in an operating state, when the voltage generated at the gate resistance element exceeds a threshold voltage; and a mask circuit provided between the gate resistance element and the determination unit, and configured to mask the voltage generated at the gate resistance element for preventing the voltage from being input to the determination unit during a predetermined mask period from a time when an input to the drive circuit is switched from the OFF signal to the ON signal to an end of the mask period. ### Claim 18 (depends on 11) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 11, wherein the drive voltage is supplied from a drive circuit connected through a control interconnection to the control electrode of the self-arc-extinguishing type semiconductor element, the drive circuit includes: a first semiconductor switching element connected between a first power supply node and the control interconnection; and a second semiconductor switching element connected between a second power supply node and the central interconnection, the drive circuit is configured to output the drive voltage for turning on the self-arc-extinguishing type semiconductor element, when the first semiconductor switching element is in an ON state, and output the drive voltage for turning off the self-arc-extinguishing type semiconductor element, when the second semiconductor switching element is in an ON state, and the second protection circuit further includes a gate resistance element connected between the first power supply node and the control interconnection, and the operation determination circuit is configured to determine whether the first protection circuit is in an operating state, based on a voltage generated at the gate resistance element. ### Claim 19 (depends on 18) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 18, wherein the operation determination circuit includes: a delay circuit configured to output a voltage which is changed with a delay relative to a change of the voltage generated at the gate resistance element, and a determination unit configured to determine that the first protection circuit is in an operating state, when the voltage which is output from the delay circuit exceeds a threshold voltage. ### Claim 20 (depends on 19) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 19, wherein the operation determination circuit further includes a voltage limitation circuit provided between the gate resistance element and the delay circuit and configured to limit a magnitude of a voltage which is input from the gate resistance element to the delay circuit. ### Claim 21 (depends on 19) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 19, wherein the delay circuit is configured as an RC filter circuit including a resistance element and a capacitor, and the RC filter circuit is configured to have a smaller time constant when the capacitor is being discharged relative to a time constant when the capacitor is being charged. ### Claim 22 (depends on 19) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 19, wherein the operation determination circuit further includes a voltage induction circuit provided between the delay circuit and the determination unit and configured to reduce a magnitude of a voltage which is input from the delay circuit to the determination unit. ### Claim 23 (depends on 18) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 18, wherein the drive circuit is configured to output the drive voltage for switching on the self-arc-extinguishing type semiconductor element and output the drive voltage for switching off the self-arc-extinguishing type semiconductor element, in response to an ON signal and an OFF signal, respectively, and the operation determination circuit includes: a determination unit configured to determine that the first protection circuit is in an operating state, when the voltage generated at the gate resistance element exceeds a threshold voltage; and a mask circuit provided between the gate resistance element and the determination unit, and configured to mask the voltage generated at the gate resistance element for preventing the voltage from being input to the determination unit during a predetermined mask period from a time when an input to the drive circuit is switched from the OFF signal to the ON signal to an end of the mask period. ### Claim 24 (depends on 10) The short-circuit protection circuit for a self-arc-extinguishing type semiconductor element according to claim 10, wherein the self-arc-extinguishing type semiconductor element is made from a semiconductor material for which silicon or silicon carbide is used.