US 11,747,216 B1
Capacitor-referenced temperature sensing
Michael H. Perrott, Nashua, NH (US); and Shungneng Lee, Sunnyvale, CA (US)
Assigned to SiTime Corporation, Santa Clara, CA (US)
Filed by SiTime Coporation, Santa Clara, CA (US)
Filed on Dec. 6, 2021, as Appl. No. 17/543,052.
Application 17/543,052 is a division of application No. 17/083,706, filed on Oct. 29, 2020, granted, now 11,226,241.
Application 17/083,706 is a division of application No. 16/205,107, filed on Nov. 29, 2018, granted, now 10,852,199, issued on Dec. 1, 2020.
Application 16/205,107 is a division of application No. 15/364,179, filed on Nov. 29, 2016, granted, now 10,175,119, issued on Jan. 8, 2019.
Application 15/364,179 is a division of application No. 14/927,864, filed on Oct. 30, 2015, granted, now 9,523,615, issued on Dec. 20, 2016.
Application 14/927,864 is a division of application No. 13/607,603, filed on Sep. 7, 2012, granted, now 9,182,295, issued on Nov. 10, 2015.
Claims priority of provisional application 61/533,149, filed on Sep. 9, 2011.
Int. Cl. G01K 7/22 (2006.01); G01K 7/16 (2006.01); H03B 5/04 (2006.01); H03B 5/30 (2006.01); H03H 9/02 (2006.01); H03L 1/02 (2006.01); G01K 7/34 (2006.01); G01K 7/18 (2006.01); G01K 7/12 (2006.01)
CPC G01K 7/226 (2013.01) [G01K 7/16 (2013.01); G01K 7/22 (2013.01); G01K 7/34 (2013.01); H03B 5/04 (2013.01); H03B 5/30 (2013.01); H03H 9/02244 (2013.01); H03L 1/02 (2013.01); G01K 7/12 (2013.01); G01K 7/186 (2013.01); G01K 2219/00 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A device to measure a value of an environmental parameter, the device comprising:
a first circuit structure having an electrical circuit parameter that varies dependent on variation in the environmental parameter to be measured;
a second circuit structure comprising at least one capacitor and a switch to cause the at least one capacitor be switched at a frequency that causes the at least one capacitor to exhibit an effective resistance that varies according to variation of the frequency, the second circuit structure characterized by an electrical circuit parameter that varies dependent on the effective resistance;
circuitry to generate a control signal dependent on a relationship between the electrical circuit parameter of the first circuit structure and the electrical circuit parameter to the second circuit structure, in a manner that adjusts the effective resistance so as to drive the relationship toward a predetermined state; and
circuitry to produce an output signal, representing measurement of the value, dependent on the control signal.