US 12,241,946 B2
Capacitor measurement
Davide Argento, Milan (IT); Orazio Pennisi, Pieve Emanuele (IT); Stefano Castorina, Milan (IT); Vanni Poletto, Milan (IT); Matteo Landini, Bareggio (IT); and Andrea Maino, Novara (IT)
Assigned to STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on Jun. 15, 2023, as Appl. No. 18/335,511.
Application 18/335,511 is a division of application No. 17/407,747, filed on Aug. 20, 2021, granted, now 11,719,761.
Prior Publication US 2023/0324475 A1, Oct. 12, 2023
Int. Cl. G01R 31/64 (2020.01); G01R 27/26 (2006.01); G01R 31/00 (2006.01)
CPC G01R 31/64 (2020.01) [G01R 27/2605 (2013.01); G01R 31/006 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for measuring an equivalent series resistor value of a capacitor, the method comprising:
having a resistor coupled to a terminal of the capacitor;
measuring a first change in voltage at the terminal of the capacitor at a first time during a discharge routine, the discharge routine comprising sinking a current through a discharge circuit coupled to the resistor from the first time to a second time;
measuring a first change in voltage across terminals of the resistor at the first time;
measuring a second change in voltage across the terminals of the resistor at the second time;
measuring a second change in voltage at the terminal of the capacitor at the second time;
computing the equivalent series resistor value as a function of a sum of the first change in voltage and the second change in voltage at the terminal of the capacitor and inversely related to a sum of voltage differences between the voltage at the terminal of the capacitor and the voltage at a second terminal of the resistor coupled to the discharge circuit at a first time and the voltage at the terminal of the capacitor and the voltage at the second terminal of the resistor at the second time; and
determining a health of the capacitor based on a difference between the computed equivalent series resistor value and a threshold value.