# US 2013/0156069 A1 · Process independent temperature sensor based on oscillator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0156069 A1 - Document ID: US20130156069A1 - Status: Published application - Kind: A1 - Application number: 13/620,594 - Filed: 2012-09-14 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Electronics and Telecommunications Research Institute - Inventors: Seok Ju Yun; Young-deuk Jeon; Tae Moon Roh; Jong-Kee Kwon; Woo Seok Yang; Jongdae Kim - Web page: https://patentgrep.com/patent/US20130156069A1 ## CPC - G01K 7/32: using change of resonant frequency of a crystal - G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00) ## Abstract The inventive concept discloses a new temperature sensor structure based on oscillator which is insensitive to a process change and improves an error rate of temperature output. The temperature sensor based on oscillator compares an oscillator circuit structure insensitive to a temperature change with an oscillator circuit structure having a frequency change in proportion to a temperature change to output a relative difference between the two oscillator circuit structures and thereby it is compensated itself. In the temperature sensor based on oscillator, a problem of performance reduction due to an external environment and a process deviation of temperature sensor is improved and an output distortion and temperature nonlinearity are effectively improved. Thus, since the temperature sensor based on oscillator has a structure of high performance, low power and low cost, it can be variously used in a detection equipment of temperature environment. ## Claims ### Claim 1 A digital temperature sensor based on oscillator comprising: a first oscillator generating a first output signal having a first temperature characteristic; a second oscillator generating a second output signal having a second temperature characteristic different from the first temperature characteristic; and a time digital convertor outputting a digital signal for which a temperature output is compensated using the first and second output signals. ### Claim 2 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein the first temperature characteristic of the first oscillator is to obtain an output frequency in proportion to a temperature change. ### Claim 3 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein when the first temperature characteristic of the first oscillator is to obtain an output frequency in proportion to a temperature change, the second temperature characteristic of the second oscillator is to obtain an output frequency insensitively to a temperature change as compared with the first temperature characteristic, and wherein when the second temperature characteristic of the second oscillator is to obtain an output frequency in proportion to a temperature change, the first temperature characteristic of the first oscillator is to obtain an output frequency insensitively to a temperature change as compared with the second temperature characteristic. ### Claim 4 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein when using a frequency of the first output signal as a counting clock, the frequency of the first output signal is higher than a frequency of the second output signal. ### Claim 5 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein a frequency convertor for dividing the frequency of the first output signal is further included between the first oscillator and the time digital convertor or between the second oscillator and the time digital convertor. ### Claim 6 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein when using a frequency of the second output signal as a counting clock, the frequency of the first output signal is lower than a frequency of the second output signal. ### Claim 7 (depends on 5) The digital temperature sensor based on oscillator of claim 5, wherein the frequency of the first output signal is equal to the frequency of the second output signal and wherein the frequency of the first output signal is divided by the frequency convertor to be used as a counting clock. ### Claim 8 (depends on 5) The digital temperature sensor based on oscillator of claim 5, further comprising an output buffer for buffering an output of the time digital convertor. ### Claim 9 (depends on 8) The digital temperature sensor based on oscillator of claim 8, further comprising a latch for latching the time digital convertor between the time digital convertor and the output buffer. ### Claim 10 (depends on 1) The digital temperature sensor based on oscillator of claim 1, wherein the time digital convertor receives the first output signal as a clock signal and receives the second output signal as a reference signal which becomes a counting target. ### Claim 11 A digital temperature sensor based on oscillator comprising: a first oscillator generating a nonlinear first output signal having a temperature proportion output characteristic; a second oscillator generating a nonlinear second output signal having a temperature independent output characteristic; and a time digital convertor outputting a digital signal for which a nonlinear distortion is compensated using the first and second output signals. ### Claim 12 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein the first oscillator is a ring oscillator including a plurality of stages. ### Claim 13 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein the second oscillator is a ring oscillator including a plurality of stages. ### Claim 14 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein when using a frequency of the first output signal as a counting clock, the frequency of the first output signal is higher than a frequency of the second output signal. ### Claim 15 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein a frequency convertor for dividing the frequency of the first output signal is further included between the first oscillator and the time digital convertor or between the second oscillator and the time digital convertor. ### Claim 16 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein when using a frequency of the second output signal as a counting clock, the frequency of the first output signal is lower than a frequency of the second output signal. ### Claim 17 (depends on 15) The digital temperature sensor based on oscillator of claim 15, wherein the frequency of the first output signal is equal to the frequency of the second output signal and wherein the frequency of the first output signal is divided by the frequency convertor to be used as a counting clock. ### Claim 18 (depends on 15) The digital temperature sensor based on oscillator of claim 15, further comprising an output buffer for buffering an output of the time digital convertor. ### Claim 19 (depends on 15, 18) The digital temperature sensor based on oscillator of claim 15 of claim 18, further comprising a latch for latching the time digital convertor between the time digital convertor and the output buffer. ### Claim 20 (depends on 11) The digital temperature sensor based on oscillator of claim 11, wherein the time digital convertor counts the second output signal by the first output signal to output a digital code value. ### Claim 21 A method of sensing a temperature comprising: preparing a first oscillator having a frequency change in proportion to a temperature change and a second oscillator insensitive to a temperature change; and counting an output frequency of the second oscillator by an output frequency of the first oscillator to output a digital code which is output-compensated itself. ### Claim 22 (depends on 21) The method of claim 21, further comprising dividing or multiplying an output frequency of the first oscillator.