# US 2023/0053720 A1 · Semiconductor module > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0053720 A1 - Document ID: US20230053720A1 - Status: Published application - Kind: A1 - Application number: 17/846,739 - Filed: 2022-06-22 - Published: 2023-02-23 - Earliest claimed: 2021-08-17 - Assignees: Fuji Electric Co., Ltd. - Applicants: Fuji Electric Co., Ltd. - Inventors: Shigemi MIYAZAWA - Web page: https://patentgrep.com/patent/US20230053720A1 ## CPC - H03K 17/08122: {in field-effect transistor switches} - H03K 17/0822: {in field-effect transistor switches} - H02H 3/093: with timing means {(in general H02H3/027; thermal delay H02H3/085; timing means for undervoltage protection H02H3/247)} - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 3/158: including plural semiconductor devices as final control devices for a single load - H03K 2217/0027: Measuring means of, e.g. currents through or voltages across the switch - 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) - 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) ## Abstract A semiconductor module including a first switching device coupled to a first line, a terminal, at which a first voltage corresponding to a first current flowing through the first switching device is generated, coupled to the first switching device, a second switching device coupled to the first line for allowing a second current corresponding to the first current to flow therethrough, a voltage generation circuit configured to apply, to a second line, a second voltage lower than a power supply voltage, a resistor, across which a third voltage corresponding to the second current is generated, coupled between the second switching device and the terminal, a reference voltage circuit coupled to the terminal for generating a fourth voltage, and a comparator circuit coupled between the first and second lines, for determining whether the first switching device is in an overcurrent state based on a comparison between the third and fourth voltages. ## Claims ### Claim 1 A semiconductor module comprising: a first switching device coupled to a first line in the semiconductor module, the first line being configured to receive a power supply voltage; a terminal coupled to the first switching device, a first voltage corresponding to a first current flowing through the first switching device being generated at the terminal while the first switching device is on; a second switching device coupled to the first line, the second switching device being configured to allow a second current corresponding to the first current to flow therethrough; a voltage generation circuit configured to apply, to a second line in the semiconductor module, a second voltage that is lower than the power supply voltage by a predetermined voltage; a resistor coupled between the second switching device and the terminal, a third voltage corresponding to the second current being generated across the resistor; a reference voltage circuit coupled to the terminal, the reference voltage circuit being configured to generate a fourth voltage; and a comparator circuit coupled between the first line and the second line, the comparator circuit being configured to determine whether the first switching device is in an overcurrent state based on a comparison between the third voltage and the fourth voltage. ### Claim 2 (depends on 1) The semiconductor module according to claim 1, further comprising a driver circuit configured to turn on and off the first switching device in response to an input signal of the semiconductor module, wherein the driver circuit turns off the first switching device in response to the comparator circuit determining that the first switching device is in the overcurrent state. ### Claim 3 (depends on 2) The semiconductor module according to claim 2, wherein the comparator circuit determines that the first switching device is in the overcurrent state when the first voltage is lower than the second voltage. ### Claim 4 (depends on 3) The semiconductor module according to claim 3, wherein the comparator circuit outputs a fifth voltage that is at a first logic level when the third voltage is lower than the fourth voltage, and at a second logic level when the first voltage is lower than the second voltage or when the third voltage is higher than the fourth voltage, and the driver circuit drives the first switching device based on the fifth voltage. ### Claim 5 (depends on 2) The semiconductor module according to claim 2, further comprising a logic circuit coupled to the comparator circuit, wherein the comparator circuit outputs a fifth voltage to the logic circuit, the fifth voltage being at a first logic level when the third voltage is higher than the fourth voltage, and at a second logic level when the third voltage is lower than the fourth voltage, the logic circuit outputs a sixth voltage at the first logic level when the first voltage is lower than the second voltage or when the third voltage is higher than the fourth voltage, and the driver circuit drives the first switching device based on the sixth voltage. ### Claim 6 (depends on 5) The semiconductor module according to claim 5, wherein the logic circuit is coupled to the reference voltage circuit and the comparator circuit. ### Claim 7 (depends on 5) The semiconductor module according to claim 5, wherein the logic circuit includes an inverting circuit coupled to the reference voltage circuit, and an OR circuit coupled to the comparator circuit and the inverting circuit. ### Claim 8 (depends on 2) The semiconductor module according to claim 2, wherein the driver circuit includes: a control signal output circuit configured to output a control signal that is based on the input signal for controlling on and off of the first switching device, irrespective of a result of the comparison by the comparator circuit, in a predetermined time period when the first switching device is turned on, and output the control signal that is based on the input signal and the result of the comparison after a lapse of the predetermined time period; a boost circuit configured to apply a driving voltage to a control electrode of the first switching device in response to the control signal upon turning on of the first switching device; and an interrupting device configured to turn off the first switching device, in response to the control signal to turn off the first switching device.