# US 11,029,365 B2 · Semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,365 B2 - Document ID: US11029365B2 - Status: Granted - Kind: B2 - Application number: 15/802,625 - Filed: 2017-11-03 - Published: 2018-05-10 - Granted: 2021-06-08 - Earliest claimed: 2016-11-09 - Assignees: Rohm Co., Ltd. - Applicants: Rohm Co., Ltd. - Inventors: Satoshi Maejima; Junichi Hagino - Web page: https://patentgrep.com/patent/US11029365B2 ## CPC - H03K 17/0822: {in field-effect transistor switches} - G01R 27/205: {Measuring contact resistance of connections, e.g. of earth connections} - G01R 31/50: Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections (testing of sparking plugs H01T13/58) - H01H 83/04: with testing means for indicating the ability of the switch or relay to function properly - H03K 17/687: the devices being field-effect transistors - H03K 19/1733: {Controllable logic circuits (H03K19/177 takes precedence)} - H10D 84/903: {comprising field effect technology} - 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) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract A semiconductor device includes an external terminal, a switching output stage that performs switching drive of a terminal voltage at the external terminal, an output control unit arranged to generate a drive signal for the switching output stage according to an input pulse signal, a counter arranged to count the number of pulses of the input pulse signal so as to generate a mask signal, a logical gate arranged to mask the input pulse signal according to the mask signal, and a comparator arranged to compare the terminal voltage with a predetermined threshold value voltage so as to generate a reset signal of the counter. ## Claims ### Claim 1 A semiconductor device comprising: an external terminal; a switching output stage arranged to perform switching drive of a terminal voltage at the external terminal; a counter arranged to count the number of pulses of an input pulse signal branched to a first path so as to generate a mask signal; a logical gate arranged to determine according to the mask signal whether to mask the input pulse signal branched to a second path or to pass through the input pulse signal branched to the second path without masking; an output control unit arranged to generate a drive signal for the switching output stage according to an output signal of the logical gate; and a comparator arranged to compare a predetermined threshold value with the terminal voltage so as to generate a reset signal of the counter, wherein the counter increments the count value when a pulse of the input pulse signal comes and resets the count value to zero when a pulse of the reset signal comes, and switches the mask signal to a first logical level when masking is enabled at a time point when the count value reaches a first set value without being reset, wherein the counter continues to count the number of pulses of the input pulse signal also after the mask signal is set to the first logical level, and when the count value reaches a second set value larger than the first set value, the mask signal is switched to a second logical level when masking is canceled, and the count value is reset to zero, wherein the counter includes a first counter unit that receives input of the input pulse signal and outputs a first pulse signal whose logical level is switched when the count value reaches the first set value, a second counter unit that is connected to a post-stage of the first counter unit and outputs a second pulse signal whose logical level is switched when the count value reaches the second set value, and a D flip-flop that receives input of the first pulse signal and fixes a third pulse signal to a predetermined logical level when the logical level of the first pulse signal is switched, the first counter unit is reset by the reset signal and the second pulse signal, the second counter unit is reset by the third pulse signal, the D flip-flop is reset by the second pulse signal, and the third pulse signal or a logically inverted signal thereof is output as the mask signal. ### Claim 2 (depends on 1) The semiconductor device according to claim 1, wherein at least one of the first set value and the second set value is a variable value that can be arbitrarily set. ### Claim 3 (depends on 1) The semiconductor device according to claim 1, wherein the switching output stage includes an upper switch connected between a power supply terminal and the external terminal, and a lower switch connected between the external terminal and a ground terminal. ### Claim 4 (depends on 3) The semiconductor device according to claim 3, wherein the output control unit generates the drive signal so as to turn off the upper switch and turn on the lower switch during a period while the input pulse signal is masked. ### Claim 5 (depends on 3) The semiconductor device according to claim 3, wherein the upper switch is a PMOSFET while the lower switch is an NMOSFET. ### Claim 6 (depends on 1) The semiconductor device according to claim 1, further comprising an output feedback unit arranged to generate the input pulse signal so that an output voltage or a feedback voltage corresponding to the output voltage matches a predetermined target value. ### Claim 7 (depends on 6) A switching power supply comprising: the semiconductor device according to claim 6; a smoothing unit arranged to smooth a terminal voltage at the external terminal of the semiconductor device so as to generate the output voltage; and a voltage dividing unit arranged to divide the output voltage so as to generate the feedback voltage. ### Claim 8 (depends on 1) The semiconductor device according to claim 1, wherein when no ground fault occurs at the external terminal, the terminal voltage is switching- driven according to ON/OFF of the switching output stage, and when a ground fault occurs at the external terminal, the terminal voltage is fixed to a ground voltage lower than the threshold value voltage regardless of ON/OFF of the switching output stage. ### Claim 9 (depends on 1) The semiconductor device according to claim 1, wherein the second counter unit receives input of the first pulse signal. ### Claim 10 (depends on 1) The semiconductor device according to claim 1, wherein the first pulse signal is a binary signal whose logical level is switched every time when the count value reaches an integer multiple of the first set value.