US 12,218,679 B2
Gain and offset diagnosis of analog-to-digital converters in sensor signal path
Dan Ioan Dumitru Stoica, Bucharest (RO); Constantin Crisu, Bucharest (RO); Constantin Stroi, Bucharest (RO); Vlad Buiculescu, Bucharest (RO); Matthias Böhm, Putzbrunn (DE); Alessandro Caspani, Villach (AT); Cesare Buffa, Villach (AT); and Franz Michael Darrer, Graz (AT)
Assigned to Infineon Technologies AG, Neubiberg (DE)
Filed by Infineon Technologies AG, Neubiberg (DE)
Filed on Dec. 27, 2022, as Appl. No. 18/146,641.
Prior Publication US 2024/0213997 A1, Jun. 27, 2024
Int. Cl. H03M 1/10 (2006.01); G10L 21/0232 (2013.01); H03M 1/06 (2006.01); H03M 1/34 (2006.01)
CPC H03M 1/34 (2013.01) [G10L 21/0232 (2013.01); H03M 1/0626 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A sensor circuit having a startup phase and an operation phase subsequent to the startup phase, the sensor circuit comprising:
a sensor configured to measure a property and generate a sensor signal based on the property, wherein the sensor signal has a frequency spectrum defined by a first frequency that is greater than zero and a second frequency that is greater than the first frequency;
a signal processing circuit comprising an analog-to-digital converter (ADC) configured to convert the sensor signal into a digital sensor signal; and
an offset diagnosis circuit coupled to an output of the ADC, wherein the offset diagnosis circuit comprises:
a first low pass filter having a first cutoff frequency less than the first frequency and configured to generate a first filtered signal based on the digital sensor signal;
an offset register configured to store a first startup signal value of the first filtered signal during the startup phase; and
an offset comparator circuit configured to set a first threshold range based on the first startup signal value and, during the operation phase, compare the first filtered signal with the first threshold range and generate a first error signal on a condition that the first filtered signal does not satisfy the first threshold range during the operation phase.