US 11,808,572 B2
Vibration rectification error correction circuit, physical quantity sensor module, structure monitoring device, and correction value adjustment method of vibration rectification error correction circuit
Masayoshi Todorokihara, Suwa (JP); and Kenta Sato, Shiojiri (JP)
Assigned to SEIKO EPSON CORPORATION
Filed by Seiko Epson Corporation, Tokyo (JP)
Filed on Apr. 26, 2019, as Appl. No. 16/395,694.
Claims priority of application No. 2018-086187 (JP), filed on Apr. 27, 2018.
Prior Publication US 2019/0331491 A1, Oct. 31, 2019
Int. Cl. G01C 19/5614 (2012.01); G01P 15/125 (2006.01); G01C 19/5719 (2012.01); G01P 15/13 (2006.01); G01H 17/00 (2006.01); G01H 3/00 (2006.01); G01P 15/10 (2006.01); G01P 15/08 (2006.01)
CPC G01C 19/5614 (2013.01) [G01C 19/5719 (2013.01); G01H 3/005 (2013.01); G01H 17/00 (2013.01); G01P 15/10 (2013.01); G01P 15/125 (2013.01); G01P 15/132 (2013.01); G01P 2015/0822 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A vibration rectification error correction circuit comprising:
a frequency delta sigma modulation circuit, the frequency delta sigma modulation circuit being configured to:
receive a reference clock signal;
receive an original sensor signal from a sensor element, the sensor element being configured to measure a physical quantity corresponding to the original sensor signal; and
generate a modulated sensor signal based on the reference clock signal and the original sensor signal, a digital value of the modulated sensor signal corresponding to a number of signal edges of the reference clock signal in a most recent one cycle of the original sensor signal, and
a first connection circuit, the first correction circuit being configured to:
receive the modulated sensor signal having the digital value;
obtain a plurality of correction values, the plurality of correction values being set based on a property of the sensor element, the plurality of correction values being used for calculating a correction of a vibration rectification error of the original sensor signal;
subtract each value of the plurality of correction values from the digital value so as to obtain a plurality of subtracted values; and
multiply each value of the plurality of subtracted values so as to obtain a product as a corrected sensor signal in which the vibration rectification error of the original sensor signal has been corrected.