US 12,146,895 B2
Robust signal path plausibility check for functional safety of a sensor
Johannes Guettinger, Lind ob Velden (AT); Bernhard Forster, Finkenstein (AT); and Simon Hainz, Villach (AT)
Assigned to Infineon Technologies AG, Neubiberg (DE)
Filed by Infineon Technologies AG, Neubiberg (DE)
Filed on Oct. 6, 2020, as Appl. No. 17/064,195.
Prior Publication US 2022/0107338 A1, Apr. 7, 2022
Int. Cl. G01P 21/02 (2006.01); G01P 3/44 (2006.01); G01R 29/08 (2006.01); G01R 31/28 (2006.01); G01R 33/00 (2006.01); G01R 35/00 (2006.01)
CPC G01P 21/02 (2013.01) [G01P 3/44 (2013.01); G01R 29/0878 (2013.01); G01R 31/2829 (2013.01); G01R 33/0029 (2013.01); G01R 35/00 (2013.01); G01R 33/0041 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
obtaining, by a monitoring device of a sensor, a first signal at a point on a first branch of a signal path of the sensor;
obtaining, by the monitoring device, a delayed first signal at a point on a branch of the first branch;
monitoring, by the monitoring device, the first signal for an occurrence of a characteristic indicated by the first signal;
monitoring, by the monitoring device, the first signal and the delayed first signal to determine whether a next occurrence of the characteristic indicated by the first signal is indicated by the first signal or by the delayed first signal;
assessing, by the monitoring device, a functionality of the signal path based on whether the next occurrence of the characteristic is indicated by the first signal or by the delayed first signal;
obtaining, by the monitoring device, a second signal at a point on a second branch of the signal path of the sensor;
monitoring, by the monitoring device, the first signal for first characteristics indicated by the first signal;
monitoring, by the monitoring device, the second signal for second characteristics indicated by the second signal;
determining, by the monitoring device and based on the monitoring of the first signal for the first characteristics and the monitoring of the second signal for the second characteristics, a quantity of first characteristics indicated by the first signal without a corresponding second characteristic being indicated by the second signal;
determining, by the monitoring device, when the quantity of first characteristics indicated by the first signal without the corresponding second characteristic being indicated by the second signal reaches a threshold quantity of first characteristics; and
assessing, by the monitoring device, the functionality of the signal path based on whether the quantity of first characteristics indicated by the first signal without a particular quantity of second characteristics being indicated by the second signal reaches the threshold quantity of first characteristics.