# US 2019/0170594 A1 · Failure determination circuit, physical quantity measurement device, electronic apparatus, and vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170594 A1 - Document ID: US20190170594A1 - Status: Published application - Kind: A1 - Application number: 15/926,043 - Filed: 2018-03-20 - Published: 2019-06-06 - Earliest claimed: 2017-03-28 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Takashi AOYAMA - Web page: https://patentgrep.com/patent/US20190170594A1 ## CPC - G01K 19/00: Testing or calibrating calorimeters - G01C 19/5607: using vibrating tuning forks (double-ended tuning forks using planar vibrating masses suspended at opposite ends G01C19/5719) - G01C 19/5726: Signal processing - G01K 15/007: {Testing} - G01K 2205/00: Application of thermometers in motors, e.g. of a vehicle - G01P 1/006: {used for thermal compensation} - G07C 5/0808: {Diagnosing performance data (testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005)} - G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00) - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) - G07C: TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE ## Abstract A failure determination circuit includes a switching circuit that receives a signal including an output voltage from a temperature sensor and a first reference voltage and outputs the signal in a time division manner, an A/D conversion circuit that A/D converts an output of the switching circuit, and a first determination circuit, and the first determination circuit determines a failure of the temperature sensor based on a signal based on a first digital signal obtained by A/D converting an output voltage from the temperature sensor by the A/D conversion circuit, a signal based on a second digital signal obtained by A/D converting the first reference voltage by the A/D conversion circuit, and temperature characteristics data based on a change in characteristics of the temperature sensor due to temperature and a change in characteristics of the first reference voltage due to temperature. ## Claims ### Claim 1 A failure determination circuit comprising: a switching circuit configured to receive a signal including an output voltage from a temperature sensor and a first reference voltage and output the signal in a time division manner; an A/D conversion circuit configured to A/D convert an output of the switching circuit; and a first determination circuit, wherein the first determination circuit determines a failure of the temperature sensor based on a signal based on a first digital signal obtained by A/D converting an output voltage from the temperature sensor by the A/D conversion circuit, a signal based on a second digital signal obtained by A/D converting the first reference voltage by the A/D conversion circuit, and temperature characteristics data based on a change in characteristics of the temperature sensor due to temperature and a change in characteristics of the first reference voltage due to temperature. ### Claim 2 (depends on 1) The failure determination circuit according to claim 1, wherein the switching circuit further receives a second reference voltage, and the change in characteristics of the first reference voltage due to temperature and the change in characteristics of the second reference voltage due to temperature are different from each other. ### Claim 3 (depends on 1) The failure determination circuit according to claim 1, wherein the switching circuit further receives a third reference voltage, and the change in characteristics of the third reference voltage due to temperature and the change in characteristics of the first reference voltage due to temperature are different from each other. ### Claim 4 (depends on 1) The failure determination circuit according to claim 1, further comprising: a memory; wherein the temperature characteristics data is stored in the memory, and the temperature characteristics data stored in the memory is changeable. ### Claim 5 (depends on 1) The failure determination circuit according to claim 1, further comprising: a second determination circuit; wherein the first reference voltage is generated based on a first power supply voltage, and the second determination circuit receives the first power supply voltage and a second power supply voltage different from the first power supply voltage and compares the first power supply voltage with the second power supply voltage to determine abnormality of the first power supply voltage. ### Claim 6 (depends on 1) A physical quantity measurement device comprising: the failure determination circuit according to claim 1. ### Claim 7 (depends on 2) A physical quantity measurement device comprising: the failure determination circuit according to claim 2. ### Claim 8 (depends on 3) A physical quantity measurement device comprising: the failure determination circuit according to claim 3. ### Claim 9 (depends on 4) A physical quantity measurement device comprising: the failure determination circuit according to claim 4. ### Claim 10 (depends on 5) A physical quantity measurement device comprising: the failure determination circuit according to claim 5. ### Claim 11 (depends on 6) The physical quantity measurement device according to claim 6, further comprising: a physical quantity measurement element; and an output correction circuit; wherein a signal based on a physical quantity measurement signal measured by the physical quantity measurement element is further input to the switching circuit, and the output correction circuit corrects a signal based on a third digital signal obtained by A/D converting the signal, which is based on the physical quantity measurement signal measured by the physical quantity measurement element, by the A/D conversion circuit with a signal based on the first digital signal obtained by A/D converting the output voltage of the temperature sensor by the A/D conversion circuit and outputs the corrected signal. ### Claim 12 (depends on 6) An electronic apparatus comprising: the physical quantity measurement device according to claim 6. ### Claim 13 (depends on 7) An electronic apparatus comprising: the physical quantity measurement device according to claim 7. ### Claim 14 (depends on 8) An electronic apparatus comprising: the physical quantity measurement device according to claim 8. ### Claim 15 (depends on 9) An electronic apparatus comprising: the physical quantity measurement device according to claim 9. ### Claim 16 (depends on 11) An electronic apparatus comprising: the physical quantity measurement device according to claim 11. ### Claim 17 (depends on 6) A vehicle comprising: the physical quantity measurement device according to claim 6. ### Claim 18 (depends on 7) A vehicle comprising: the physical quantity measurement device according to claim 7. ### Claim 19 (depends on 8) A vehicle comprising: the physical quantity measurement device according to claim 8. ### Claim 20 (depends on 11) A vehicle comprising: the physical quantity measurement device according to claim 11.